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Head-to-head comparison

GPT-5.5 vs. Gemini 3.5 Flash

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

shared result series
218
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 3.5 Flash
AttributeGPT-5.5Gemini 3.5 Flash
ProviderOpenAIGoogle
ReleasedApr 2026May 19, 2026
AvailabilityActiveActive
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 3.5 Flash
Price typeGPT-5.5Gemini 3.5 Flash
API input$5 ≤272K / $10 >272K$1.5
API output$30 ≤272K / $45 >272K$9
Cache read$0.5 ≤272K / $1 >272K$0.15
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 3.5 Flash
API inputUSD per 1M tokens, base tier
GPT-5.5$5
Gemini 3.5 FlashLower price$1.5
API outputUSD per 1M tokens, base tier
GPT-5.5$30
Gemini 3.5 FlashLower price$9
Cache readUSD per 1M tokens, base tier
GPT-5.5$0.5
Gemini 3.5 FlashLower price$0.15

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 3.5 Flash
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
Gemini 3.5 FlashGoogleDirect from developerStandard API$1.5$9Source07/30/2026
GoogleVia OpenRoutergoogle-vertex/global$1.5$9Source09/06/2026
GoogleVia OpenRoutergoogle-vertex/global/flexLowest listed price: $0.75Lowest listed price: $4.5Source09/06/2026
GoogleVia OpenRoutergoogle-vertex/global/priority$2.7$16.2Source09/06/2026
GoogleVia OpenRoutergoogle-vertex/us$1.65$9.9Source09/06/2026
Google AI StudioVia OpenRoutergoogle-ai-studio$1.5$9Source09/06/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/flexLowest listed price: $0.75Lowest listed price: $4.5Source09/06/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/priority$2.7$16.2Source09/06/2026

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.

255075100CodingReasoningMathematicsKnowledgeFinanceLegalAgentic tasksMultimodal
GPT-5.5
Gemini 3.5 Flash
Coding: 99.6 / 70.6 (6 benchmark families)
Reasoning: 100 / 99.3 (2 benchmark families)
Mathematics: 99.6 / 99.3 (1 benchmark family)
Knowledge: 99.2 / 99.8 (2 benchmark families)
Finance: 98.2 / 98.3 (6 benchmark families)
Legal: 100 / 84.5 (4 benchmark families)
Agentic tasks: 97.9 / 94.3 (4 benchmark families)
Multimodal: 100 / 100 (1 benchmark family)

71 matched rows from 28 benchmark families were considered. The radar shows 8 of 14 comparable categories.

GPT-5.5Gemini 3.5 Flash
Code MigrationOverall. Higher is better. No documented setup difference
GPT-5.5Winner45.161 %
Gemini 3.5 Flash26.745 %
CorpFin v2Overall. Higher is better. No documented setup difference
GPT-5.5Winner68.415 %
Gemini 3.5 Flash64.686 %
CyberBenchOverall. Higher is better. No documented setup difference
GPT-5.5Winner80.508 %
Gemini 3.5 Flash69.331 %
EMBOverall. Higher is better. No documented setup difference
GPT-5.5Winner64.543 %
Gemini 3.5 Flash63.548 %
Finance Agent (v2)Overall. Higher is better. No documented setup difference
GPT-5.551.76 %
Gemini 3.5 FlashWinner57.861 %
GAIA ReliabilityAccuracy. Higher is better. No documented setup difference
GPT-5.562.8 %
Gemini 3.5 FlashWinner79.2 %
GPQA DiamondOverall. Higher is better. No documented setup difference
GPT-5.5Winner93.182 %
Gemini 3.5 Flash92.676 %
Harvey's Legal Agent BenchmarkOverall · Task fully resolved. Higher is better. No documented setup difference
GPT-5.5Winner3.75 %
Gemini 3.5 Flash2.5 %
Legal Research BenchOverall · All-pass. Higher is better. No documented setup difference
GPT-5.5Winner40.385 %
Gemini 3.5 Flash30.769 %
LegalBenchOverall. Higher is better. No documented setup difference
GPT-5.5Winner86.515 %
Gemini 3.5 Flash83.602 %
LiveCodeBench v6Overall. Higher is better. No documented setup difference
GPT-5.585.296 %
Gemini 3.5 FlashWinner87.604 %
LMArena Text, Style ControlOverall. Higher is better. No documented setup difference
GPT-5.5No clear lead1,482.334
Gemini 3.5 Flash1,479.148

Key to the marks:better valuebetter, but not conclusivetie

Benchmark scores for GPT-5.5 and Gemini 3.5 Flash
Benchmark and taskGPT-5.5Gemini 3.5 FlashSource
Code MigrationOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner45.161 %
26.745 %
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 %
64.686 %
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 %
69.331 %
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 %
63.548 %
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
51.76 %
Winner57.861 %
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 %
Winner79.2 %
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
Winner93.182 %
92.676 %
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 %
2.5 %
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 %
30.769 %
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
Winner86.515 %
83.602 %
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 %
Winner87.604 %
Vals AI
Source details
Data as of: 09/01/2026
LMArena Text, Style ControlOverall
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-high, Reasoning: high, Harness: Arena text, style control
Gemini 3.5 Flash: Snapshot: gemini-3.5-flash-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 63,265 anonymous pairwise votes.Gemini 3.5 Flash: Style-controlled Arena rating from 33,874 anonymous pairwise votes.
No clear lead1,482.334
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.
1,479.148
95% confidence interval: ±4.345The 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 %
Winner55.825 %
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 %
76.574 %
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 %
Winner89.515 %
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
Tie88.266 %
Tie88.266 %
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
Winner68.76 %
68.124 %
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 %
59.472 %
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 %
49.885 %
Vals AI
Source details
Data as of: 09/03/2026
SkillsBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands
Winner62.209 %
52.737 %
Vals AI
Source details
Data as of: 09/01/2026
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 %
74.366 %
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 %
74.157 %
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 %
53.079 %
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 %
62.928 %
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 %
48.683 %
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 %
Winner80.8 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value36.882 %
17.175 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value65.618 %
62.821 %
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 %
81.034 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
64.681 %
Higher measured value69.788 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
45.74 %
Higher measured value54.869 %
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
Winner0.75 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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value93.434 %
91.414 %
Vals AI
Source details
Data as of: 08/09/2026
Harvey's Legal Agent BenchmarkAntitrust Competition · Criteria passed
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: criteria pass rateScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
82.246 %
Higher measured value84.42 %
Vals AI
Source details
Data as of: 08/07/2026
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value53.03 %
43.939 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value89.644 %
81.939 %
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 3.5 Flash: 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 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-high, Reasoning: high, Harness: Arena text, style control
Gemini 3.5 Flash: Snapshot: gemini-3.5-flash-high, Reasoning: high, Harness: Arena text, style controlGPT-5.5: Style-controlled Arena rating from 12,594 anonymous pairwise votes.Gemini 3.5 Flash: Style-controlled Arena rating from 6,750 anonymous pairwise votes.
Winner1,489.993
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.
1,465.666
95% confidence interval: ±7.938The 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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value94.003 %
93.863 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
76.153 %
Higher measured value77.504 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value9.5 %
1.5 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 30,000 tokens
Higher measured value40.476 %
38.492 %
Vals AI
Source details
Data as of: 08/09/2026
SkillsBenchNo Skills
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Harness: OpenHands, Output limit: 128,000 tokens
Gemini 3.5 Flash: Reasoning: high, Harness: OpenHands, Temperature: 1, Output limit: 65,536 tokens
Higher measured value49.875 %
40.971 %
Vals AI
Source details
Data as of: 08/07/2026
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value91.753 %
86.598 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value65.495 %
61.897 %
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 3.5 Flash: 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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
83.333 %
Higher measured value100 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value69.58 %
64.569 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value69.58 %
64.569 %
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
0.78 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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value70 %
55.455 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value70.047 %
66.667 %
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 %
57.627 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
Higher measured value81.227 %
80.921 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
39.562 %
Higher measured value45.706 %
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.
Tie0.8 rating points
Tie0.8 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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
92.929 %
Higher measured value93.939 %
Vals AI
Source details
Data as of: 08/09/2026
Harvey's Legal Agent BenchmarkAntitrust Competition · Task fully resolved
Test details
Test setup not documented as identicalNo direct winnerVersion: 1Metric: task resolution rateScoring: Higher is betterGPT-5.5: Reasoning: xhigh, Output limit: 128,000 tokens
Gemini 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
No direct winner0 %
No direct winner0 %
Vals AI
Source details
Data as of: 08/07/2026
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
86.669 %
Higher measured value87.126 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
83.836 %
Higher measured value88.675 %
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 3.5 Flash: Reasoning: high, Temperature: 1, Output limit: 65,536 tokens
69.714 %
Higher measured value73.143 %
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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