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Head-to-head comparison

GPT-5.5 vs. Gemini 3.1 Pro Preview

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

shared result series
197
distinct benchmarks
29
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 Gemini 3.1 Pro Preview
AttributeGPT-5.5Gemini 3.1 Pro Preview
ProviderOpenAIGoogle
ReleasedApr 2026Feb 19, 2026
AvailabilityActivePreview
Model typeProprietaryProprietary
ParametersNot publishedNot published
ArchitectureNot publishedNot published
Context window1,050,000 tokens1,048,576 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 Gemini 3.1 Pro Preview
Price typeGPT-5.5Gemini 3.1 Pro Preview
API input$5 ≤272K / $10 >272K$2 ≤200K / $4 >200K
API output$30 ≤272K / $45 >272K$12 ≤200K / $18 >200K
Cache read$0.5 ≤272K / $1 >272K$0.2 ≤200K / $0.4 >200K
Cache write (5 min.)Not listedNot listed
Cache write (1 hr.)Not listedNot listed
Price verified07/30/2026 Source07/30/2026 Source
GPT-5.5Gemini 3.1 Pro Preview
API inputUSD per 1M tokens, base tier
GPT-5.5$5
Gemini 3.1 Pro PreviewLower price$2
API outputUSD per 1M tokens, base tier
GPT-5.5$30
Gemini 3.1 Pro PreviewLower price$12
Cache readUSD per 1M tokens, base tier
GPT-5.5$0.5
Gemini 3.1 Pro PreviewLower price$0.2

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 Gemini 3.1 Pro Preview
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$33Source09/07/2026
AzureVia OpenRouterazure$5$30Source09/07/2026
AzureVia OpenRouterazure/eu$5.5$33Source09/07/2026
AzureVia OpenRouterazure/us$5.5$33Source09/07/2026
OpenAIVia OpenRouteropenai$5$30Source09/07/2026
OpenAIVia OpenRouteropenai/fast$12.5$75Source09/07/2026
OpenAIVia OpenRouteropenai/flexLowest listed price: $2.5Lowest listed price: $15Source09/07/2026
Gemini 3.1 Pro PreviewGoogleDirect from developerUp to 200,000 context tokens$2$12Source07/30/2026
GoogleDirect from developerAbove 200,000 context tokens$4$18Source07/30/2026
GoogleVia OpenRoutergoogle-vertex/global$2$12Source09/07/2026
GoogleVia OpenRoutergoogle-vertex/global/flexLowest listed price: $1Lowest listed price: $6Source09/07/2026
GoogleVia OpenRoutergoogle-vertex/global/priority$3.6$21.6Source09/07/2026
Google AI StudioVia OpenRoutergoogle-ai-studio$2$12Source09/07/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/flexLowest listed price: $1Lowest listed price: $6Source09/07/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/priority$3.6$21.6Source09/07/2026

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.

255075100CodingReasoningMathematicsKnowledgeFinanceLegalAgentic tasksMultimodal
GPT-5.5
Gemini 3.1 Pro Preview
Coding: 99.3 / 63.3 (6 benchmark families)
Reasoning: 98.6 / 100 (2 benchmark families)
Mathematics: 100 / 99 (1 benchmark family)
Knowledge: 98 / 100 (2 benchmark families)
Finance: 99.8 / 92.6 (6 benchmark families)
Legal: 99.6 / 62.8 (4 benchmark families)
Agentic tasks: 97.5 / 96.6 (3 benchmark families)
Multimodal: 100 / 99.9 (1 benchmark family)

71 matched rows from 28 benchmark families were considered. The radar shows 8 of 15 comparable categories.

GPT-5.5Gemini 3.1 Pro Preview
BrowseCompOverall. Higher is better. No documented setup difference
GPT-5.584.4 %
Gemini 3.1 Pro PreviewWinner85.9 %
Code MigrationOverall. Higher is better. No documented setup difference
GPT-5.5Winner45.161 %
Gemini 3.1 Pro Preview17.313 %
CorpFin v2Overall. Higher is better. No documented setup difference
GPT-5.5Winner68.415 %
Gemini 3.1 Pro Preview64.491 %
CyberBenchOverall. Higher is better. No documented setup difference
GPT-5.5Winner80.508 %
Gemini 3.1 Pro Preview36.441 %
EMBOverall. Higher is better. No documented setup difference
GPT-5.5Winner64.543 %
Gemini 3.1 Pro Preview52.616 %
Finance Agent (v2)Overall. Higher is better. No documented setup difference
GPT-5.5Winner51.76 %
Gemini 3.1 Pro Preview42.982 %
GAIA ReliabilityAccuracy. Higher is better. No documented setup difference
GPT-5.562.8 %
Gemini 3.1 Pro PreviewWinner76.2 %
GPQA DiamondOverall. Higher is better. No documented setup difference
GPT-5.593.182 %
Gemini 3.1 Pro PreviewWinner95.454 %
Harvey's Legal Agent BenchmarkOverall · Task fully resolved. Higher is better. No documented setup difference
GPT-5.5Winner3.75 %
Gemini 3.1 Pro Preview0 %
Legal Research BenchOverall · All-pass. Higher is better. No documented setup difference
GPT-5.5Winner40.385 %
Gemini 3.1 Pro Preview20.673 %
LegalBenchOverall. Higher is better. No documented setup difference
GPT-5.586.515 %
Gemini 3.1 Pro PreviewWinner87.398 %
LiveCodeBench v6Overall. Higher is better. No documented setup difference
GPT-5.585.296 %
Gemini 3.1 Pro PreviewWinner88.485 %

Key to the marks:better valuebetter, but not conclusivetie

Benchmark scores for GPT-5.5 and Gemini 3.1 Pro Preview
Benchmark and taskGPT-5.5Gemini 3.1 Pro PreviewSource
BrowseCompOverall
Test details
No documented difference in the test setupVersion: 1,266 tasksMetric: accuracyScoring: Higher is betterCross-vendor comparison table with browsing tools. Exact agent systems differ.
84.4 %
Editorial selection from the vendor table, not a complete extract of the comparison cohort.
Winner85.9 %
Editorial selection from the vendor table, not a complete extract of the comparison cohort.		OpenAI
Source details
Data as of: 07/09/2026
Code MigrationOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner45.161 %
17.313 %
Vals AI
Source details
Data as of: 09/03/2026
CorpFin v2Overall
Test details
No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better
Winner68.415 %
64.491 %
Vals AI
Source details
Data as of: 08/12/2026
CyberBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner80.508 %
36.441 %
Vals AI
Source details
Data as of: 09/01/2026
EMBOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner64.543 %
52.616 %
Vals AI
Source details
Data as of: 09/03/2026
Finance Agent (v2)Overall
Test details
No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better
Winner51.76 %
42.982 %
Vals AI
Source details
Data as of: 09/03/2026
GAIA ReliabilityAccuracy
Test details
No documented difference in the test setupVersion: final leak-cleaned public validation setMetric: exact-match accuracyScoring: Higher is betterSettings: Agent: HAL Reliability, Harness: HAL Reliability165 GAIA tasks with repeated runs and perturbations. HAL does not publish cost for this evaluation.
62.8 %
Winner76.2 %
Princeton HAL
Source details
Data as of: 08/06/2026
GPQA DiamondOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
93.182 %
Winner95.454 %
Vals AI
Source details
Data as of: 09/01/2026
Harvey's Legal Agent BenchmarkOverall · Task fully resolved
Test details
No documented difference in the test setupVersion: 1Metric: task resolution rateScoring: Higher is better
Winner3.75 %
0 %
Vals AI
Source details
Data as of: 09/03/2026
Legal Research BenchOverall · All-pass
Test details
No documented difference in the test setupVersion: 1Metric: all-pass rateScoring: Higher is better
Winner40.385 %
20.673 %
Vals AI
Source details
Data as of: 09/03/2026
LegalBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
86.515 %
Winner87.398 %
Vals AI
Source details
Data as of: 09/01/2026
LiveCodeBench v6Overall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
85.296 %
Winner88.485 %
Vals AI
Source details
Data as of: 09/01/2026
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
Gemini 3.1 Pro Preview: Snapshot: gemini-3.1-pro-preview, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 64,686 anonymous pairwise votes.Gemini 3.1 Pro Preview: Style-controlled Arena rating from 102,763 anonymous pairwise votes.
1,477.235
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.
Winner1,486.746
95% confidence interval: ±3.217The 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
MedCodeOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
49.1 %
Winner59.062 %
Vals AI
Source details
Data as of: 09/03/2026
MedScribeOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner86.868 %
76.114 %
Vals AI
Source details
Data as of: 09/03/2026
MMLU-ProOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
88.144 %
Winner90.987 %
Vals AI
Source details
Data as of: 09/01/2026
MMMU-ProOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner88.266 %
88.208 %
Vals AI
Source details
Data as of: 09/01/2026
MortgageTaxOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
68.76 %
Winner69.396 %
Vals AI
Source details
Data as of: 09/01/2026
ProgramBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner0.5 %
0 %
Vals AI
Source details
Data as of: 09/01/2026
Public Benefits Bench v1.1Overall
Test details
No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is better
Winner60.893 %
53.789 %
Vals AI
Source details
Data as of: 09/01/2026
SAGEOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner51.532 %
48.677 %
Vals AI
Source details
Data as of: 09/03/2026
SWE-bench VerifiedOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner82.6 %
78.8 %
Vals AI
Source details
Data as of: 09/01/2026
TaxEval v2Overall
Test details
No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better
Winner74.98 %
72.882 %
Vals AI
Source details
Data as of: 09/01/2026
Terminal-Bench 2.0Overall
Test details
No documented difference in the test setupVersion: 2.0Metric: accuracyScoring: Higher is better
Winner73.202 %
67.416 %
Vals AI
Source details
Data as of: 06/04/2026
Terminal-Bench 2.1Overall
Test details
No documented difference in the test setupVersion: 2.1Metric: accuracyScoring: Higher is better
Winner76.404 %
70.787 %
Vals AI
Source details
Data as of: 09/03/2026
Vals IndexOverall
Test details
No documented difference in the test setupVersion: 2Metric: weighted index scoreScoring: Higher is better
Winner57.411 %
41.903 %
Vals AI
Source details
Data as of: 09/03/2026
Vals Multimodal IndexOverall
Test details
No documented difference in the test setupVersion: 1.2Metric: weighted index scoreScoring: Higher is better
Winner68.071 %
56.068 %
Vals AI
Source details
Data as of: 08/11/2026
Vibe Code Bench v1.1Overall
Test details
No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands
Winner69.847 %
32.034 %
Vals AI
Source details
Data as of: 09/03/2026
τ-bench Airline CleanAccuracy
Test details
No documented difference in the test setupVersion: 26-task cleaned subsetMetric: task success rateScoring: Higher is betterSettings: Agent: HAL Reliability, Harness: HAL Reliability26 cleaned airline tasks. Princeton HAL recomputed every metric from scratch on this subset.
79.5 %
Winner82.1 %
Princeton HAL
Source details
Data as of: 08/05/2026
Code MigrationCLI
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value36.882 %
10.833 %
Vals AI
Source details
Data as of: 08/09/2026
CorpFin v2Exact Pages
Test details
Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value65.618 %
60.839 %
Vals AI
Source details
Data as of: 08/06/2026
CyberBenchPatch
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner81.356 %
69.492 %
Vals AI
Source details
Data as of: 08/03/2026
EMBComps
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value64.681 %
44.505 %
Vals AI
Source details
Data as of: 08/06/2026
Finance Agent (v2)Adjustments
Test details
Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value45.74 %
38.361 %
Vals AI
Source details
Data as of: 08/06/2026
GAIA ReliabilityConsistency
Test details
No documented difference in the test setupVersion: final leak-cleaned public validation setMetric: aggregate consistencyScoring: Higher is betterSettings: Agent: HAL Reliability, Harness: HAL Reliability165 GAIA tasks with repeated runs and perturbations. HAL does not publish cost for this evaluation.
0.61 rating points
Winner0.76 rating points
Princeton HAL
Source details
Data as of: 08/06/2026
GPQA DiamondFew-Shot CoT
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,535 tokens
93.434 %
Higher measured value95.96 %
Vals AI
Source details
Data as of: 08/09/2026
Legal Research BenchAdministrative / Regulatory · All-pass
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: all-pass rateScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value53.03 %
24.242 %
Vals AI
Source details
Data as of: 08/06/2026
LegalBenchConclusion Tasks
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value89.644 %
89.257 %
Vals AI
Source details
Data as of: 08/09/2026
LiveCodeBench v6Easy
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
98.447 %
Higher measured value99.068 %
Vals AI
Source details
Data as of: 08/09/2026
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
Gemini 3.1 Pro Preview: Snapshot: gemini-3.1-pro-preview, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 63,265 anonymous pairwise votes.Gemini 3.1 Pro Preview: Style-controlled Arena rating from 102,763 anonymous pairwise votes.
1,482.334
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.
Higher measured value1,486.746
95% confidence interval: ±3.217The 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
MMLU-ProBiology
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,535 tokens
94.003 %
Higher measured value95.258 %
Vals AI
Source details
Data as of: 08/09/2026
MortgageTaxNumerical Extraction
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
76.153 %
Higher measured value76.391 %
Vals AI
Source details
Data as of: 08/09/2026
ProgramBenchAlmost Resolved
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value9.5 %
1 %
Vals AI
Source details
Data as of: 08/09/2026
SAGEAutomata
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Temperature: 1, Output limit: 30,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 30,000 tokens
Higher measured value40.476 %
32.143 %
Vals AI
Source details
Data as of: 08/09/2026
SWE-bench Verified<15 min fix
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value91.753 %
88.66 %
Vals AI
Source details
Data as of: 08/08/2026
TaxEval v2Correctness
Test details
Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,535 tokens
Higher measured value65.495 %
60.749 %
Vals AI
Source details
Data as of: 08/09/2026
Terminal-Bench 2.0Easy
Test details
Test setup not documented as identicalNo direct winnerVersion: 2.0Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: high, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
85 %
Higher measured value100 %
Vals AI
Source details
Data as of: 06/04/2026
Terminal-Bench 2.1Easy
Test details
Test setup not documented as identicalNo direct winnerVersion: 2.1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: high, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
83.333 %
Higher measured value91.667 %
Vals AI
Source details
Data as of: 08/06/2026
Vals IndexCorpFin v2
Test details
Test setup not documented as identicalNo direct winnerVersion: 1.2Metric: benchmark scoreScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value69.58 %
65.734 %
Vals AI
Source details
Data as of: 08/09/2026
Vals Multimodal IndexCorpFin v2
Test details
Test setup not documented as identicalNo direct winnerVersion: 1.2Metric: benchmark scoreScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value69.58 %
65.734 %
Vals AI
Source details
Data as of: 08/09/2026
τ-bench Airline CleanConsistency
Test details
No documented difference in the test setupVersion: 26-task cleaned subsetMetric: aggregate consistencyScoring: Higher is betterSettings: Agent: HAL Reliability, Harness: HAL Reliability26 cleaned airline tasks. Princeton HAL recomputed every metric from scratch on this subset.
Winner0.84 rating points
0.81 rating points
Princeton HAL
Source details
Data as of: 08/05/2026
Code MigrationCOBOL
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value70 %
36.753 %
Vals AI
Source details
Data as of: 08/09/2026
CorpFin v2Max Fitting Context
Test details
Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value70.047 %
66.9 %
Vals AI
Source details
Data as of: 08/06/2026
CyberBenchPoC
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner79.661 %
3.39 %
Vals AI
Source details
Data as of: 08/03/2026
EMBDataroom
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value81.227 %
79.17 %
Vals AI
Source details
Data as of: 08/06/2026
Finance Agent (v2)All-Pass
Test details
Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value39.562 %
30.879 %
Vals AI
Source details
Data as of: 08/06/2026
GAIA ReliabilityPredictability
Test details
No documented difference in the test setupVersion: final leak-cleaned public validation setMetric: aggregate predictabilityScoring: Higher is betterSettings: Agent: HAL Reliability, Harness: HAL Reliability165 GAIA tasks with repeated runs and perturbations. HAL does not publish cost for this evaluation.
Winner0.8 rating points
0.78 rating points
Princeton HAL
Source details
Data as of: 08/06/2026
GPQA DiamondZero-Shot CoT
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,535 tokens
92.929 %
Higher measured value94.949 %
Vals AI
Source details
Data as of: 08/09/2026
Legal Research BenchAdministrative / Regulatory · Weighted partial credit
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: weighted partial-credit scoreScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value86.669 %
79.215 %
Vals AI
Source details
Data as of: 08/06/2026
LegalBenchInterpretation Tasks
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value83.836 %
83.823 %
Vals AI
Source details
Data as of: 08/09/2026
LiveCodeBench v6Hard
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
69.714 %
Higher measured value76.571 %
Vals AI
Source details
Data as of: 08/09/2026
LMArena Text, Style ControlBusiness, management and finance
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
Gemini 3.1 Pro Preview: Snapshot: gemini-3.1-pro-preview, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 12,904 anonymous pairwise votes.Gemini 3.1 Pro Preview: Style-controlled Arena rating from 20,283 anonymous pairwise votes.
No clear lead1,485.915
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.
1,476.52
95% confidence interval: ±5.472The 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
MMLU-ProBusiness
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,535 tokens
92.015 %
Higher measured value93.409 %
Vals AI
Source details
Data as of: 08/09/2026
MortgageTaxSemantic Extraction
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.1 Pro Preview: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
61.367 %
Higher measured value62.401 %
Vals AI
Source details
Data as of: 08/09/2026

Key to the marks:better valuebetter, but not conclusivetie

How to read this comparison

Winning one benchmark is not an overall verdict

Your workload, budget, and required context length matter most. A coding benchmark says little about visual understanding or agent performance.

The standard price table uses direct developer rates. The provider comparison labels OpenRouter endpoints, regions, and special tariffs separately.

Every result links to its measurement source and retrieval date. Labels distinguish vendor reports, official benchmark leaderboards, and independent evaluations. Disputed or archived results are excluded.

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