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Head-to-head comparison

Claude Sonnet 5 vs. GPT-5.6 Luna

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

196

shared result series

25

distinct benchmarks

2026-08-16

latest retrieval

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Specifications and cost

General specifications and standard API pricing

Undisclosed parameter counts and knowledge cutoffs stay marked as unavailable. The table shows direct standard token pricing, including documented context tiers. Batch, fast, priority, regional surcharges, tool calls, and cloud platform pricing are excluded.

Specifications and API pricing for Claude Sonnet 5 and GPT-5.6 Luna
AttributeClaude Sonnet 5GPT-5.6 Luna
ProviderAnthropicOpenAI
ReleasedJun 30, 2026Jun 26, 2026
AvailabilityActiveActive
Model typeProprietaryProprietary
ParametersNot publishedNot published
ArchitectureNot publishedNot published
Context window1,000,000 tokens1,050,000 tokens
Knowledge cutoffJanuary 2026February 16, 2026
Technical sourcesModel, ContextModel, Context, Knowledge cutoff
API pricing per 1M tokens
API input$2$0.2 ≤272K / $0.4 >272K
API output$10$1.2 ≤272K / $1.8 >272K
Cache read$0.2$0.02 ≤272K / $0.04 >272K
Cache write (5 min.)$2.5$0.25 ≤272K / $0.5 >272K
Cache write (1 hr.)$4Not listed
Price verified08/11/2026Source08/11/2026Source
Claude Sonnet 5GPT-5.6 Luna
API inputUSD per 1M tokens, base tier
Claude Sonnet 5$2
GPT-5.6 Luna$0.2Lower price
API outputUSD per 1M tokens, base tier
Claude Sonnet 5$10
GPT-5.6 Luna$1.2Lower price
Cache readUSD per 1M tokens, base tier
Claude Sonnet 5$0.2
GPT-5.6 Luna$0.02Lower price

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.

196 shared result series
Claude Sonnet 5GPT-5.6 Luna
Arena Text, Style ControlOverall. Higher is better. Test setup not documented as identical
Claude Sonnet 51,462.192 arena pointsHigher measured value
GPT-5.6 Luna1,450.561 arena points
Code MigrationOverall. Higher is better. No documented setup difference
Claude Sonnet 544.392 %
GPT-5.6 Luna44.55 %Winner
CorpFin v2Overall. Higher is better. No documented setup difference
Claude Sonnet 566.977 %Winner
GPT-5.6 Luna64.219 %
EMBOverall. Higher is better. No documented setup difference
Claude Sonnet 566.316 %
GPT-5.6 Luna67.116 %Winner
Finance Agent (v2)Overall. Higher is better. No documented setup difference
Claude Sonnet 553.909 %
GPT-5.6 Luna55.044 %Winner
GPQA DiamondOverall. Higher is better. No documented setup difference
Claude Sonnet 588.889 %
GPT-5.6 Luna91.666 %Winner
Harvey's Legal Agent BenchmarkOverall · Task fully resolved. Higher is better. No documented setup difference
Claude Sonnet 55 %Winner
GPT-5.6 Luna1.25 %
Legal Research BenchOverall · All-pass. Higher is better. No documented setup difference
Claude Sonnet 541.827 %Winner
GPT-5.6 Luna36.538 %
LegalBenchOverall. Higher is better. No documented setup difference
Claude Sonnet 583.922 %
GPT-5.6 Luna84.034 %Winner
MedCodeOverall. Higher is better. No documented setup difference
Claude Sonnet 547.54 %Winner
GPT-5.6 Luna42.391 %
MedScribeOverall. Higher is better. No documented setup difference
Claude Sonnet 576.054 %
GPT-5.6 Luna84.391 %Winner
MMLU-ProOverall. Higher is better. No documented setup difference
Claude Sonnet 587.545 %Winner
GPT-5.6 Luna86.036 %
Benchmark scores for Claude Sonnet 5 and GPT-5.6 Luna
Benchmark and taskClaude Sonnet 5GPT-5.6 LunaComparabilitySource
Arena Text, Style ControlOverall
1,462.192 arena pointsHigher measured value
95% confidence interval: ±5.168The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,450.561 arena points
95% confidence interval: ±5.636The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
style-control-v1style-controlled Bradley-Terry ratingHigher is betterCohort: lmarena-text-style-control:2026-08-12:overallTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Snapshot: claude-sonnet-5-high, Reasoning: high, Harness: Arena text, style control
GPT-5.6 Luna: Snapshot: gpt-5.6-luna-xhigh, Reasoning: xhigh, Harness: Arena text, style control
Claude Sonnet 5: Style-controlled Arena rating from 23,138 anonymous pairwise votes.GPT-5.6 Luna: Style-controlled Arena rating from 16,419 anonymous pairwise votes.
ArenaType: Official benchmark leaderboardLeaderboard updated: 2026-08-12Import ID: lmarena-eeedf9209373a7f9b324bfb839e7b02fedacd1e5-1611ed64f3f1Retrieved 2026-08-16
Code MigrationOverall
44.392 %
44.55 %Winner
1accuracyHigher is betterCohort: vals-code-migration:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-13Import ID: vals-code-migration-2026-08-16-107652dc6bfcRetrieved 2026-08-16
CorpFin v2Overall
66.977 %Winner
64.219 %
2accuracyHigher is betterCohort: vals-corp-fin-v2:2:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-corp_fin_v2-2026-08-16-45bbf84f57abRetrieved 2026-08-16
EMBOverall
66.316 %
67.116 %Winner
1accuracyHigher is betterCohort: vals-emb:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-13Import ID: vals-emb-2026-08-16-68d5d1d47a97Retrieved 2026-08-16
Finance Agent (v2)Overall
53.909 %
55.044 %Winner
2accuracyHigher is betterCohort: vals-finance-agent-v2:2:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-14Import ID: vals-fabv2-2026-08-16-8853da43085dRetrieved 2026-08-16
GPQA DiamondOverall
88.889 %
91.666 %Winner
1accuracyHigher is betterCohort: vals-gpqa:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-gpqa-2026-08-16-7f8363eaa2dbRetrieved 2026-08-16
Harvey's Legal Agent BenchmarkOverall · Task fully resolved
5 %Winner
1.25 %
1task resolution rateHigher is betterCohort: vals-legal-agent-benchmark:1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-14Import ID: vals-hlab-2026-08-16-bae90566df2fRetrieved 2026-08-16
Legal Research BenchOverall · All-pass
41.827 %Winner
36.538 %
1all-pass rateHigher is betterCohort: vals-legal-research:1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-14Import ID: vals-legal_research-2026-08-16-af296c00ecaaRetrieved 2026-08-16
LegalBenchOverall
83.922 %
84.034 %Winner
1accuracyHigher is betterCohort: vals-legal-bench:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-legal_bench-2026-08-16-d5b3b1b2b5c8Retrieved 2026-08-16
MedCodeOverall
47.54 %Winner
42.391 %
1accuracyHigher is betterCohort: vals-medcode:1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-medcode-2026-08-16-524f7f474eacRetrieved 2026-08-16
MedScribeOverall
76.054 %
84.391 %Winner
1accuracyHigher is betterCohort: vals-medscribe:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-medscribe-2026-08-16-c385354a7e62Retrieved 2026-08-16
MMLU-ProOverall
87.545 %Winner
86.036 %
1accuracyHigher is betterCohort: vals-mmlu-pro:1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-mmlu_pro-2026-08-16-e14d5bb3a34cRetrieved 2026-08-16
MMMU-ProOverall
83.006 %
85.029 %Winner
1accuracyHigher is betterCohort: vals-mmmu:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-mmmu-2026-08-16-37c9a8c7e21fRetrieved 2026-08-16
MortgageTaxOverall
70.032 %Winner
67.29 %
1accuracyHigher is betterCohort: vals-mortgage-tax:1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-mortgage_tax-2026-08-16-e78c985dbb1cRetrieved 2026-08-16
ProgramBenchOverall
0 %Tie
0 %Tie
1accuracyHigher is betterCohort: vals-programbench:1:overallNo documented setup differenceTieClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-13Import ID: vals-programbench-2026-08-16-08d9727662ddRetrieved 2026-08-16
ProofBenchOverall
77 %Winner
60 %
1.1accuracyHigher is betterCohort: vals-proof-bench:1.1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-14Import ID: vals-proof_bench-2026-08-16-14232db24de1Retrieved 2026-08-16
Public Benefits Bench v1.1Overall
66.035 %Winner
61.164 %
1.1accuracyHigher is betterCohort: vals-snap:1.1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-public-benefits-bench-2026-08-16-7ce68123c502Retrieved 2026-08-16
SAGEOverall
48.925 %Winner
44.22 %
1accuracyHigher is betterCohort: vals-sage:1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-sage-2026-08-16-a416dd25affbRetrieved 2026-08-16
SkillsBenchOverall
46.476 %
60.447 %Winner
1accuracyHigher is betterCohort: vals-skillsbench:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: Harness: OpenHands
GPT-5.6 Luna: Harness: OpenHands
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-13Import ID: vals-skillsbench-2026-08-16-4917a67268d2Retrieved 2026-08-16
SWE-bench VerifiedOverall
79.6 %
93 %Winner
1accuracyHigher is betterCohort: vals-swebench:1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-swebench-2026-08-16-c133071b8167Retrieved 2026-08-16
TaxEval v2Overall
75.634 %
76.166 %Winner
2accuracyHigher is betterCohort: vals-tax-eval-v2:2:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-12Import ID: vals-tax_eval_v2-2026-08-16-5bbd495dac53Retrieved 2026-08-16
Terminal-Bench 2.1Overall
74.532 %
79.026 %Winner
2.1accuracyHigher is betterCohort: vals-terminal-bench-2-1:2.1:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-13Import ID: vals-terminal-bench-2-1-2026-08-16-b3f38c18bea4Retrieved 2026-08-16
Vals IndexOverall
59.61 %
59.881 %Winner
2weighted index scoreHigher is betterCohort: vals-vals-index:2:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-14Import ID: vals-vals_index-2026-08-16-ab641d89d6edRetrieved 2026-08-16
Vals Multimodal IndexOverall
68.826 %
69.058 %Winner
1.2weighted index scoreHigher is betterCohort: vals-vals-multimodal-index:1.2:overallNo documented setup differenceWinner: GPT-5.6 LunaClaude Sonnet 5: No further settings disclosed
GPT-5.6 Luna: No further settings disclosed
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-11Import ID: vals-vals_multimodal_index-2026-08-16-9f3ebb221408Retrieved 2026-08-16
Vibe Code Bench v1.1Overall
81.325 %Winner
77.055 %
1.1accuracyHigher is betterCohort: vals-vibe-code-bench:1.1:overallNo documented setup differenceWinner: Claude Sonnet 5Claude Sonnet 5: Harness: OpenHands
GPT-5.6 Luna: Harness: OpenHands
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-13Import ID: vals-vibe-code-2026-08-16-a73c9770bcc4Retrieved 2026-08-16
Arena Text, Style ControlBusiness, management and finance
1,464.884 arena points
95% confidence interval: ±9.253The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,465.32 arena pointsHigher measured value
95% confidence interval: ±11.098The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
style-control-v1style-controlled Bradley-Terry ratingHigher is betterCohort: lmarena-text-style-control:2026-08-12:industry_business_and_management_and_financial_operationsTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Snapshot: claude-sonnet-5-high, Reasoning: high, Harness: Arena text, style control
GPT-5.6 Luna: Snapshot: gpt-5.6-luna-xhigh, Reasoning: xhigh, Harness: Arena text, style control
Claude Sonnet 5: Style-controlled Arena rating from 4,692 anonymous pairwise votes.GPT-5.6 Luna: Style-controlled Arena rating from 3,171 anonymous pairwise votes.
ArenaType: Official benchmark leaderboardLeaderboard updated: 2026-08-12Import ID: lmarena-eeedf9209373a7f9b324bfb839e7b02fedacd1e5-1611ed64f3f1Retrieved 2026-08-16
Code MigrationCLI
36.332 %Higher measured value
36.067 %
1accuracyHigher is betterCohort: vals-code-migration:1:cliTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-code-migration-2026-08-11-3a2d5ce718a3Retrieved 2026-08-11
CorpFin v2Exact Pages
63.869 %Higher measured value
63.52 %
2accuracyHigher is betterCohort: vals-corp-fin-v2:2:exact_pagesTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-corp_fin_v2-2026-08-11-d9e58d191cd9Retrieved 2026-08-11
EMBComps
69.384 %Higher measured value
54.573 %
1accuracyHigher is betterCohort: vals-emb:1:compsTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-emb-2026-08-11-e3c855e236e4Retrieved 2026-08-11
Finance Agent (v2)Adjustments
48.715 %
52.027 %Higher measured value
2accuracyHigher is betterCohort: vals-finance-agent-v2:2:adjustmentsTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-fabv2-2026-08-11-3e5c93a1857cRetrieved 2026-08-11
GPQA DiamondFew-Shot CoT
87.374 %
92.424 %Higher measured value
1accuracyHigher is betterCohort: vals-gpqa:1:diamond_few_shot_cotTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-gpqa-2026-08-11-d3325290a404Retrieved 2026-08-11
Harvey's Legal Agent BenchmarkAntitrust Competition · Criteria passed
88.768 %Higher measured value
85.145 %
1criteria pass rateHigher is betterCohort: vals-legal-agent-benchmark:1:criteria_pass_rate__antitrust_competitionTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-07Import ID: vals-hlab-2026-08-11-ea11b6e53414Retrieved 2026-08-11
Legal Research BenchAdministrative / Regulatory · All-pass
54.545 %Higher measured value
48.485 %
1all-pass rateHigher is betterCohort: vals-legal-research:1:administrative_regulatoryTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-legal_research-2026-08-11-326cf7aaca58Retrieved 2026-08-11
LegalBenchConclusion Tasks
89.555 %Higher measured value
88.864 %
1accuracyHigher is betterCohort: vals-legal-bench:1:conclusion_tasksTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-legal_bench-2026-08-11-836e5e44618eRetrieved 2026-08-11
MMLU-ProBiology
93.584 %Higher measured value
93.305 %
1accuracyHigher is betterCohort: vals-mmlu-pro:1:biologyTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-mmlu_pro-2026-08-11-b8e53828d746Retrieved 2026-08-11
MortgageTaxNumerical Extraction
78.696 %Higher measured value
75.596 %
1accuracyHigher is betterCohort: vals-mortgage-tax:1:numerical_extractionTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-mortgage_tax-2026-08-11-5ea6eef3e482Retrieved 2026-08-11
ProgramBenchAlmost Resolved
13.5 %Higher measured value
9 %
1accuracyHigher is betterCohort: vals-programbench:1:almostTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-programbench-2026-08-11-b6f8959fbdfeRetrieved 2026-08-11
SAGEAutomata
34.92 %Higher measured value
31.35 %
1accuracyHigher is betterCohort: vals-sage:1:automataTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 30,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 30,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-sage-2026-08-11-f1f79f6d8af3Retrieved 2026-08-11
SkillsBenchNo Skills
35.123 %
45.189 %Higher measured value
1accuracyHigher is betterCohort: vals-skillsbench:1:no_skillsTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Harness: OpenHands, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Harness: OpenHands, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-07Import ID: vals-skillsbench-2026-08-11-351bec9d0e01Retrieved 2026-08-11
SWE-bench Verified<15 min fix
83.505 %
96.392 %Higher measured value
1accuracyHigher is betterCohort: vals-swebench:1:<15 min fixTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-08Import ID: vals-swebench-2026-08-11-a6212cd857d8Retrieved 2026-08-11
TaxEval v2Correctness
64.023 %
66.558 %Higher measured value
2accuracyHigher is betterCohort: vals-tax-eval-v2:2:correctnessTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-tax_eval_v2-2026-08-11-d05a40bf446fRetrieved 2026-08-11
Terminal-Bench 2.1Easy
100 %Higher measured value
83.333 %
2.1accuracyHigher is betterCohort: vals-terminal-bench-2-1:2.1:easyTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-terminal-bench-2-1-2026-08-11-8f0ebd72a609Retrieved 2026-08-11
Vals IndexCorpFin v2
67.949 %Higher measured value
65.035 %
1.2benchmark scoreHigher is betterCohort: vals-vals-index:1.2:corp_fin_v2Test setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-vals_index-2026-08-11-e79d08d59249Retrieved 2026-08-11
Vals Multimodal IndexCorpFin v2
67.949 %Higher measured value
65.035 %
1.2benchmark scoreHigher is betterCohort: vals-vals-multimodal-index:1.2:corp_fin_v2Test setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-vals_multimodal_index-2026-08-11-fa704862df19Retrieved 2026-08-11
Arena Text, Style ControlChinese
1,501.752 arena pointsHigher measured value
95% confidence interval: ±15.966The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,485.14 arena points
95% confidence interval: ±18.537The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
style-control-v1style-controlled Bradley-Terry ratingHigher is betterCohort: lmarena-text-style-control:2026-08-12:chineseTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Snapshot: claude-sonnet-5-high, Reasoning: high, Harness: Arena text, style control
GPT-5.6 Luna: Snapshot: gpt-5.6-luna-xhigh, Reasoning: xhigh, Harness: Arena text, style control
Claude Sonnet 5: Style-controlled Arena rating from 1,508 anonymous pairwise votes.GPT-5.6 Luna: Style-controlled Arena rating from 1,179 anonymous pairwise votes.
ArenaType: Official benchmark leaderboardLeaderboard updated: 2026-08-12Import ID: lmarena-eeedf9209373a7f9b324bfb839e7b02fedacd1e5-1611ed64f3f1Retrieved 2026-08-16
Code MigrationCOBOL
68.571 %
70 %Higher measured value
1accuracyHigher is betterCohort: vals-code-migration:1:cobolTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-code-migration-2026-08-11-3a2d5ce718a3Retrieved 2026-08-11
CorpFin v2Max Fitting Context
69.114 %Higher measured value
64.103 %
2accuracyHigher is betterCohort: vals-corp-fin-v2:2:max_fitting_contextTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-corp_fin_v2-2026-08-11-d9e58d191cd9Retrieved 2026-08-11
EMBDataroom
84.909 %Higher measured value
83.009 %
1accuracyHigher is betterCohort: vals-emb:1:dataroomTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-emb-2026-08-11-e3c855e236e4Retrieved 2026-08-11
Finance Agent (v2)All-Pass
42.084 %
43.285 %Higher measured value
2accuracyHigher is betterCohort: vals-finance-agent-v2:2:all_passTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-fabv2-2026-08-11-3e5c93a1857cRetrieved 2026-08-11
GPQA DiamondZero-Shot CoT
90.404 %
90.909 %Higher measured value
1accuracyHigher is betterCohort: vals-gpqa:1:diamond_zero_shot_cotTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-gpqa-2026-08-11-d3325290a404Retrieved 2026-08-11
Harvey's Legal Agent BenchmarkAntitrust Competition · Task fully resolved
0 %No direct winner
0 %No direct winner
1task resolution rateHigher is betterCohort: vals-legal-agent-benchmark:1:antitrust_competitionTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-07Import ID: vals-hlab-2026-08-11-ea11b6e53414Retrieved 2026-08-11
Legal Research BenchAdministrative / Regulatory · Weighted partial credit
87.81 %Higher measured value
87.513 %
1weighted partial-credit scoreHigher is betterCohort: vals-legal-research:1:weighted_pass__administrative_regulatoryTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-legal_research-2026-08-11-326cf7aaca58Retrieved 2026-08-11
LegalBenchInterpretation Tasks
81.412 %
82.142 %Higher measured value
1accuracyHigher is betterCohort: vals-legal-bench:1:interpretation_tasksTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-legal_bench-2026-08-11-836e5e44618eRetrieved 2026-08-11
MMLU-ProBusiness
91.635 %Higher measured value
91.001 %
1accuracyHigher is betterCohort: vals-mmlu-pro:1:businessTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-mmlu_pro-2026-08-11-b8e53828d746Retrieved 2026-08-11
MortgageTaxSemantic Extraction
61.367 %Higher measured value
58.983 %
1accuracyHigher is betterCohort: vals-mortgage-tax:1:semantic_extractionTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-mortgage_tax-2026-08-11-5ea6eef3e482Retrieved 2026-08-11
ProgramBenchFully Resolved
0 %No direct winner
0 %No direct winner
1accuracyHigher is betterCohort: vals-programbench:1:strictTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-programbench-2026-08-11-b6f8959fbdfeRetrieved 2026-08-11
SAGELinear Algebra
68.999 %Higher measured value
63.216 %
1accuracyHigher is betterCohort: vals-sage:1:linear_algebraTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 30,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 30,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-sage-2026-08-11-f1f79f6d8af3Retrieved 2026-08-11
SkillsBenchWith Skills
46.476 %
60.447 %Higher measured value
1accuracyHigher is betterCohort: vals-skillsbench:1:with_skillsTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Harness: OpenHands, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Harness: OpenHands, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-07Import ID: vals-skillsbench-2026-08-11-351bec9d0e01Retrieved 2026-08-11
SWE-bench Verified>4 hours
66.667 %No direct winner
66.667 %No direct winner
1accuracyHigher is betterCohort: vals-swebench:1:>4 hoursTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-08Import ID: vals-swebench-2026-08-11-a6212cd857d8Retrieved 2026-08-11
TaxEval v2Stepwise Reasoning
87.244 %Higher measured value
85.773 %
2accuracyHigher is betterCohort: vals-tax-eval-v2:2:stepwise_reasoningTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-tax_eval_v2-2026-08-11-d05a40bf446fRetrieved 2026-08-11
Terminal-Bench 2.1Hard
57.778 %
70 %Higher measured value
2.1accuracyHigher is betterCohort: vals-terminal-bench-2-1:2.1:hardTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-06Import ID: vals-terminal-bench-2-1-2026-08-11-8f0ebd72a609Retrieved 2026-08-11
Vals IndexFinance Agent v2
51.979 %
55.555 %Higher measured value
1.2benchmark scoreHigher is betterCohort: vals-vals-index:1.2:finance_agentTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-vals_index-2026-08-11-e79d08d59249Retrieved 2026-08-11
Vals Multimodal IndexFinance Agent v2
51.979 %
55.555 %Higher measured value
1.2benchmark scoreHigher is betterCohort: vals-vals-multimodal-index:1.2:finance_agentTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Compute: max, Temperature: 1, Output limit: 128,000 tokens
GPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens
Vals AIType: Independent evaluationLeaderboard updated: 2026-08-09Import ID: vals-vals_multimodal_index-2026-08-11-fa704862df19Retrieved 2026-08-11
Arena Text, Style ControlCoding
1,522.518 arena pointsHigher measured value
95% confidence interval: ±8.191The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
1,498.496 arena points
95% confidence interval: ±9.171The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.
style-control-v1style-controlled Bradley-Terry ratingHigher is betterCohort: lmarena-text-style-control:2026-08-12:codingTest setup not documented as identicalNo direct winnerClaude Sonnet 5: Snapshot: claude-sonnet-5-high, Reasoning: high, Harness: Arena text, style control
GPT-5.6 Luna: Snapshot: gpt-5.6-luna-xhigh, Reasoning: xhigh, Harness: Arena text, style control
Claude Sonnet 5: Style-controlled Arena rating from 6,492 anonymous pairwise votes.GPT-5.6 Luna: Style-controlled Arena rating from 4,743 anonymous pairwise votes.
ArenaType: Official benchmark leaderboardLeaderboard updated: 2026-08-12Import ID: lmarena-eeedf9209373a7f9b324bfb839e7b02fedacd1e5-1611ed64f3f1Retrieved 2026-08-16

The table shows 64 diversified result series from 196 shared results. This prevents one benchmark with many subtasks from crowding out every other test.

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.

Prices use official API rates per 1M tokens. Web subscriptions and cloud platform surcharges can differ.

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.