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Head-to-head comparison

GPT-5.5 vs. Mistral Medium 3.5

Compare published benchmark results from matching versions and cohorts, API pricing, and technical specifications. Any documented test setup differences remain visible.

shared result series
56
distinct benchmarks
1
latest retrieval
2026-09-04

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Specifications

General specifications

Release date, availability, context window, architecture, and published parameter counts at a glance. Undisclosed details remain marked as unavailable.

Specifications for GPT-5.5 and Mistral Medium 3.5
AttributeGPT-5.5Mistral Medium 3.5
ProviderOpenAIMistral AI
ReleasedApr 2026Apr 28, 2026
AvailabilityActiveActive
Model typeProprietaryOpen Weights
ParametersNot publishedNot published
ArchitectureNot publishedNot published
Context window1,050,000 tokens256,000 tokens
Knowledge cutoffDecember 1, 2025Not published
Technical sourcesModelModel

Pricing

API pricing compared

The table compares official standard API rates per 1M tokens, including published cache pricing. Batch, fast, priority, regional surcharges, tool calls, and cloud platform pricing are excluded.

API pricing for GPT-5.5 and Mistral Medium 3.5
Price typeGPT-5.5Mistral Medium 3.5
API input$5 ≤272K / $10 >272K$1.5
API output$30 ≤272K / $45 >272K$7.5
Cache read$0.5 ≤272K / $1 >272KNot listed
Cache write (5 min.)Not listedNot listed
Cache write (1 hr.)Not listedNot listed
Price verified07/30/2026 Source07/30/2026 Source
GPT-5.5Mistral Medium 3.5
API inputUSD per 1M tokens, base tier
GPT-5.5$5
Mistral Medium 3.5Lower price$1.5
API outputUSD per 1M tokens, base tier
GPT-5.5$30
Mistral Medium 3.5Lower price$7.5

Key to the marks:better valuebetter, but not conclusivetie

Pricing by provider

Direct developer pricing and provider endpoint tariffs routed through OpenRouter are listed separately. Prices are in USD per 1M tokens. Context-dependent direct tiers plus regional, Flex, Priority, and other OpenRouter tariffs remain individually identifiable.

Provider pricing for GPT-5.5 and Mistral Medium 3.5
ModelProviderPurchase route and tariffInput per 1M tokensOutput per 1M tokensSource
GPT-5.5OpenAIDirect from developerUp to 272,000 context tokens$5$30Source07/30/2026
OpenAIDirect from developerAbove 272,000 context tokens$10$45Source07/30/2026
Amazon BedrockVia OpenRouteramazon-bedrock/us-east-1$5.5$33Source09/06/2026
AzureVia OpenRouterazure$5$30Source09/06/2026
AzureVia OpenRouterazure/eu$5.5$33Source09/06/2026
AzureVia OpenRouterazure/us$5.5$33Source09/06/2026
OpenAIVia OpenRouteropenai$5$30Source09/06/2026
OpenAIVia OpenRouteropenai/fast$12.5$75Source09/06/2026
OpenAIVia OpenRouteropenai/flexLowest listed price: $2.5Lowest listed price: $15Source09/06/2026
Mistral Medium 3.5Mistral AIDirect from developerStandard APILowest listed price: $1.5Lowest listed price: $7.5Source07/30/2026
MistralVia OpenRoutermistralLowest listed price: $1.5Lowest listed price: $7.5Source09/06/2026
MistralVia OpenRoutermistral/eu$1.65$8.25Source09/06/2026
MistralVia OpenRoutermistral/zdrLowest listed price: $1.5Lowest listed price: $7.5Source09/06/2026

Performance

Shared benchmarks

Only published results with the same benchmark version, task, metric, and comparison cohort are paired. Different reasoning levels, agents, harnesses, or output limits appear directly in the table.

Capability profile from matched benchmarks

Each axis averages directly matched benchmark families. A value of 100 means the stronger value within this pair, not a universal quality score.

255075100CodingReasoningMathematicsKnowledgeFinanceLegalHealthGeneral
GPT-5.5
Mistral Medium 3.5
Coding: 100 / 98 (1 benchmark family)
Reasoning: 100 / 96.3 (1 benchmark family)
Mathematics: 100 / 95.7 (1 benchmark family)
Knowledge: 100 / 96.4 (1 benchmark family)
Finance: 100 / 96.3 (1 benchmark family)
Legal: 100 / 96.8 (1 benchmark family)
Health: 100 / 95.8 (1 benchmark family)
General: 100 / 96.2 (1 benchmark family)

28 matched rows from 1 benchmark families were considered. The radar shows 8 of 8 comparable categories.

GPT-5.5Mistral Medium 3.5
LMArena Text, Style ControlOverall. Higher is better. No documented setup difference
GPT-5.5Winner1,477.235
Mistral Medium 3.51,426.98
LMArena Text, Style ControlOverall. Higher is better. Test setup not documented as identical
GPT-5.5Higher measured value1,482.334
Mistral Medium 3.51,426.98
LMArena Text, Style ControlBusiness, management and finance. Higher is better. No documented setup difference
GPT-5.5Winner1,485.915
Mistral Medium 3.51,431.113
LMArena Text, Style ControlBusiness, management and finance. Higher is better. Test setup not documented as identical
GPT-5.5Higher measured value1,489.993
Mistral Medium 3.51,431.113
LMArena Text, Style ControlChinese. Higher is better. No documented setup difference
GPT-5.5Winner1,530.095
Mistral Medium 3.51,448.299
LMArena Text, Style ControlChinese. Higher is better. Test setup not documented as identical
GPT-5.5Higher measured value1,515.679
Mistral Medium 3.51,448.299
LMArena Text, Style ControlCoding. Higher is better. No documented setup difference
GPT-5.5Winner1,508.939
Mistral Medium 3.51,478.845
LMArena Text, Style ControlCoding. Higher is better. Test setup not documented as identical
GPT-5.5Higher measured value1,520.129
Mistral Medium 3.51,478.845
LMArena Text, Style ControlCreative writing. Higher is better. No documented setup difference
GPT-5.5Winner1,448.376
Mistral Medium 3.51,396.971
LMArena Text, Style ControlCreative writing. Higher is better. Test setup not documented as identical
GPT-5.5Higher measured value1,452.482
Mistral Medium 3.51,396.971
LMArena Text, Style ControlEnglish. Higher is better. No documented setup difference
GPT-5.5Winner1,482.081
Mistral Medium 3.51,444.656
LMArena Text, Style ControlEnglish. Higher is better. Test setup not documented as identical
GPT-5.5Higher measured value1,484.772
Mistral Medium 3.51,444.656

Key to the marks:better valuebetter, but not conclusivetie

Benchmark scores for GPT-5.5 and Mistral Medium 3.5
Benchmark and taskGPT-5.5Mistral Medium 3.5Source
LMArena Text, Style ControlOverall
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 64,686 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 11,017 anonymous pairwise votes.
Winner1,477.235
95% confidence interval: ±3.839The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,426.98
95% confidence interval: ±6.556The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlOverall
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 63,265 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 11,017 anonymous pairwise votes.
Higher measured value1,482.334
95% confidence interval: ±3.856The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,426.98
95% confidence interval: ±6.556The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlBusiness, management and finance
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 12,904 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 2,148 anonymous pairwise votes.
Winner1,485.915
95% confidence interval: ±6.577The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,431.113
95% confidence interval: ±13.17The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlBusiness, management and finance
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 12,594 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 2,148 anonymous pairwise votes.
Higher measured value1,489.993
95% confidence interval: ±6.59The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,431.113
95% confidence interval: ±13.17The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlChinese
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,552 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 500 anonymous pairwise votes.
Winner1,530.095
95% confidence interval: ±11.053The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,448.299
95% confidence interval: ±26.61The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlChinese
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,648 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 500 anonymous pairwise votes.
Higher measured value1,515.679
95% confidence interval: ±10.674The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,448.299
95% confidence interval: ±26.61The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlCoding
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 18,325 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 3,079 anonymous pairwise votes.
Winner1,508.939
95% confidence interval: ±5.848The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,478.845
95% confidence interval: ±11.157The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlCoding
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 17,606 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 3,079 anonymous pairwise votes.
Higher measured value1,520.129
95% confidence interval: ±5.918The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,478.845
95% confidence interval: ±11.157The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlCreative writing
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 11,878 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,862 anonymous pairwise votes.
Winner1,448.376
95% confidence interval: ±6.88The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,396.971
95% confidence interval: ±14.389The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlCreative writing
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 11,556 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,862 anonymous pairwise votes.
Higher measured value1,452.482
95% confidence interval: ±6.902The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,396.971
95% confidence interval: ±14.389The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlEnglish
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 29,547 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 5,299 anonymous pairwise votes.
Winner1,482.081
95% confidence interval: ±4.938The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,444.656
95% confidence interval: ±8.682The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlEnglish
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 28,840 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 5,299 anonymous pairwise votes.
Higher measured value1,484.772
95% confidence interval: ±4.944The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,444.656
95% confidence interval: ±8.682The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlEntertainment, sports and media
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 15,289 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 2,453 anonymous pairwise votes.
Winner1,446.376
95% confidence interval: ±6.282The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,396.875
95% confidence interval: ±12.491The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlEntertainment, sports and media
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 14,828 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 2,453 anonymous pairwise votes.
Higher measured value1,450.494
95% confidence interval: ±6.344The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,396.875
95% confidence interval: ±12.491The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlExcluding ties
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 49,327 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 8,299 anonymous pairwise votes.
Winner1,486.307
95% confidence interval: ±5.005The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,421.17
95% confidence interval: ±8.686The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlExcluding ties
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 47,980 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 8,299 anonymous pairwise votes.
Higher measured value1,493.228
95% confidence interval: ±5.003The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,421.17
95% confidence interval: ±8.686The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlExpert prompts
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 6,796 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,110 anonymous pairwise votes.
Winner1,511.055
95% confidence interval: ±8.262The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,438.278
95% confidence interval: ±17.831The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlExpert prompts
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 6,546 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,110 anonymous pairwise votes.
Higher measured value1,513.567
95% confidence interval: ±8.306The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,438.278
95% confidence interval: ±17.831The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlFrench
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 2,369 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 438 anonymous pairwise votes.
Winner1,501.604
95% confidence interval: ±14.559The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,436.08
95% confidence interval: ±30.551The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlFrench
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 2,328 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 438 anonymous pairwise votes.
Higher measured value1,494.639
95% confidence interval: ±14.565The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,436.08
95% confidence interval: ±30.551The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlGerman
Test details
No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 1,012 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 170 anonymous pairwise votes.
No clear lead1,491.677
95% confidence interval: ±20.229The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,442.607
95% confidence interval: ±44.317The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlGerman
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 974 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 170 anonymous pairwise votes.
Higher measured value1,473.396
95% confidence interval: ±20.184The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,442.607
95% confidence interval: ±44.317The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlHard prompts
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 42,992 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 7,154 anonymous pairwise votes.
Winner1,498.125
95% confidence interval: ±4.517The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,445.592
95% confidence interval: ±7.857The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlHard prompts
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 41,441 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 7,154 anonymous pairwise votes.
Higher measured value1,501.683
95% confidence interval: ±4.543The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,445.592
95% confidence interval: ±7.857The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlHard prompts, English
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 20,195 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 3,629 anonymous pairwise votes.
Winner1,498.824
95% confidence interval: ±5.695The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,458.246
95% confidence interval: ±10.39The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlHard prompts, English
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 19,465 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 3,629 anonymous pairwise votes.
Higher measured value1,499.763
95% confidence interval: ±5.725The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,458.246
95% confidence interval: ±10.39The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlInstruction following
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 22,401 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 3,561 anonymous pairwise votes.
Winner1,473.969
95% confidence interval: ±5.476The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,422.491
95% confidence interval: ±10.335The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlInstruction following
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 21,691 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 3,561 anonymous pairwise votes.
Higher measured value1,478.507
95% confidence interval: ±5.531The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,422.491
95% confidence interval: ±10.335The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlKorean
Test details
No documented difference in the test setupNo clear leadVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 1,094 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 178 anonymous pairwise votes.
No clear lead1,427.974
95% confidence interval: ±19.644The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,394.42
95% confidence interval: ±44.572The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlKorean
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 1,090 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 178 anonymous pairwise votes.
Higher measured value1,446.278
95% confidence interval: ±19.47The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,394.42
95% confidence interval: ±44.572The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlLegal and government
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 5,331 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 839 anonymous pairwise votes.
Winner1,485.929
95% confidence interval: ±9.075The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,437.785
95% confidence interval: ±21.302The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlLegal and government
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 5,130 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 839 anonymous pairwise votes.
Higher measured value1,495.297
95% confidence interval: ±9.236The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,437.785
95% confidence interval: ±21.302The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlLife, physical and social science
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 10,700 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,823 anonymous pairwise votes.
Winner1,495.773
95% confidence interval: ±6.831The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,433.494
95% confidence interval: ±14.359The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlLife, physical and social science
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 10,554 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,823 anonymous pairwise votes.
Higher measured value1,498.539
95% confidence interval: ±6.867The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,433.494
95% confidence interval: ±14.359The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlLonger queries
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 29,781 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 4,661 anonymous pairwise votes.
Winner1,484.838
95% confidence interval: ±5.2The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,430.723
95% confidence interval: ±9.428The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlLonger queries
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 28,638 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 4,661 anonymous pairwise votes.
Higher measured value1,488.354
95% confidence interval: ±5.257The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,430.723
95% confidence interval: ±9.428The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMath
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,230 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 539 anonymous pairwise votes.
Winner1,501.81
95% confidence interval: ±11.02The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,429.582
95% confidence interval: ±24.872The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMath
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,161 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 539 anonymous pairwise votes.
Higher measured value1,490.657
95% confidence interval: ±10.928The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,429.582
95% confidence interval: ±24.872The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMathematical professions
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,601 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 597 anonymous pairwise votes.
Winner1,500.216
95% confidence interval: ±10.861The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,442.192
95% confidence interval: ±23.932The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMathematical professions
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 3,535 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 597 anonymous pairwise votes.
Higher measured value1,505.572
95% confidence interval: ±10.806The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,442.192
95% confidence interval: ±23.932The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMedicine and healthcare
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 4,840 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 802 anonymous pairwise votes.
Winner1,485.8
95% confidence interval: ±9.564The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,423.47
95% confidence interval: ±21.791The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMedicine and healthcare
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 4,726 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 802 anonymous pairwise votes.
Higher measured value1,477.659
95% confidence interval: ±9.561The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,423.47
95% confidence interval: ±21.791The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMulti-turn
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 11,272 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,803 anonymous pairwise votes.
Winner1,482.216
95% confidence interval: ±6.865The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,431.302
95% confidence interval: ±14.433The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlMulti-turn
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 10,902 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,803 anonymous pairwise votes.
Higher measured value1,490.033
95% confidence interval: ±6.973The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,431.302
95% confidence interval: ±14.433The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlNon-English
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 35,138 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 5,718 anonymous pairwise votes.
Winner1,466.636
95% confidence interval: ±4.653The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,406.687
95% confidence interval: ±8.36The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlNon-English
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 34,424 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 5,718 anonymous pairwise votes.
Higher measured value1,474.665
95% confidence interval: ±4.693The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,406.687
95% confidence interval: ±8.36The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlPolish
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 1,133 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 226 anonymous pairwise votes.
Winner1,470.019
95% confidence interval: ±18.213The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,407.955
95% confidence interval: ±38.858The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlPolish
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 1,091 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 226 anonymous pairwise votes.
Higher measured value1,479.14
95% confidence interval: ±18.375The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,407.955
95% confidence interval: ±38.858The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlRussian
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 6,486 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,143 anonymous pairwise votes.
Winner1,479.174
95% confidence interval: ±8.197The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,415.692
95% confidence interval: ±17.832The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlRussian
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 6,457 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 1,143 anonymous pairwise votes.
Higher measured value1,484.259
95% confidence interval: ±8.185The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,415.692
95% confidence interval: ±17.832The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlSoftware and IT services
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 25,850 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 4,320 anonymous pairwise votes.
Winner1,504.177
95% confidence interval: ±5.202The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,470.76
95% confidence interval: ±9.541The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlSoftware and IT services
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 25,147 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 4,320 anonymous pairwise votes.
Higher measured value1,510.903
95% confidence interval: ±5.208The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,470.76
95% confidence interval: ±9.541The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlSpanish
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 1,953 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 377 anonymous pairwise votes.
Winner1,462.461
95% confidence interval: ±14.956The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,386.845
95% confidence interval: ±32.418The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlSpanish
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 1,837 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 377 anonymous pairwise votes.
Higher measured value1,467.712
95% confidence interval: ±15.152The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,386.845
95% confidence interval: ±32.418The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlWriting, literature and language
Test details
No documented difference in the test setupVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 16,528 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 2,734 anonymous pairwise votes.
Winner1,465.967
95% confidence interval: ±6.056The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,405.944
95% confidence interval: ±11.74The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlWriting, literature and language
Test details
Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.5: Snapshot: gpt-5.5-high, Reasoning: high, Harness: Arena text, style control
Mistral Medium 3.5: Snapshot: mistral-medium-3.5, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 16,173 anonymous pairwise votes.Mistral Medium 3.5: Style-controlled Arena rating from 2,734 anonymous pairwise votes.
Higher measured value1,472.012
95% confidence interval: ±6.081The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,405.944
95% confidence interval: ±11.74The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.		LMArena
Source details
Data as of: 09/01/2026

Key to the marks:better valuebetter, but not conclusivetie

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