BenchLeader

Claude Sonnet 4.6 vs GPT-5.6 Sol

Verdict
  • GPT-5.6 Sol (high) leads on quality: 68.2 vs 60.4.
  • Claude Sonnet 4.6 is stronger in human preference, maths, reasoning.
  • GPT-5.6 Sol (high) is stronger in agents & tools, coding, composite, instruction following, knowledge, long context, multimodal.
  • Claude Sonnet 4.6 is 1.3× cheaper ($6.00 vs $8.00 per 1M blended).
  • GPT-5.6 Sol (high) streams 1.4× faster (59 vs 42 tokens per second).
MetricClaude Sonnet 4.6GPT-5.6 Sol (high)
BenchLeader Index60.468.2
Agents & tools score54.687.9
Coding score57.172.4
Composite score67.582.7
Human preference score62.0
Instruction following score56.967.8
Knowledge score62.373.8
Long context score66.667.4
Maths score62.7
Multimodal score60.666.4
Reasoning score65.263.3
Blended price $/M$6.00$8.00
Output speed42 tok/s59 tok/s
Time to first answer2.2 s31.0 s
Context window1M1M
GPQA Diamond87.4%
OTIS Mock AIME85.8%
SWE-bench Verified (Epoch)75.2%
Terminal-Bench53.4%
SciCode56.9%
WeirdML88.8%
FrontierCode24.3%
Epoch Capabilities Index152.3
LMArena Text1472
LMArena Hard Prompts1504
LMArena Coding1528
LMArena WebDev1521
LMArena Vision1282
LMArena Agent-1
AA Intelligence Index30.442.5
IFBench56.6%69.2%
AA-LCR80.0%81.7%
MMMU-Pro73.3%81.8%
AA-Omniscience12.220.4
Terminal-Bench Hard53.0%62.1%
GPQA Diamond (AA)87.5%92.8%
Humanity's Last Exam (AA)33.6%46.0%
SciCode (AA)50.1%57.8%
τ²-Bench Telecom (AA)79.5%83.3%
AIME (Vals)92.3%
LiveCodeBench82.1%
MMLU-Pro87.3%
LegalBench82.1%
CorpFin65.3%
TaxEval77.1%
MedQA92.1%
Terminal-Bench 2.1 (Vals)57.3%
SWE-bench (Vals)77.4%
GPQA Diamond (Vals)85.6%
Vals Index50.6
MCP Atlas69.5%
EnigmaEval37.1%
EQ-Bench 41207
ARC-AGI-197.0%
ARC-AGI-285.4%
ARC-AGI-32.2%

Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.

Claude Sonnet 4.6 vs GPT-5.6 Sol: questions

Is Claude Sonnet 4.6 better than GPT-5.6 Sol?
GPT-5.6 Sol (high) leads on quality: 68.2 vs 60.4. The BenchLeader Index combines every independent quality benchmark; GPT-5.6 Sol (high) is ahead overall as of 2026-09-10, but check the category scores for your use.
Is Claude Sonnet 4.6 better than GPT-5.6 Sol for coding?
GPT-5.6 Sol scores higher in coding (72 vs 57 on the category index, where 50 is average).
Is Claude Sonnet 4.6 better than GPT-5.6 Sol for agentic tasks?
GPT-5.6 Sol scores higher in agentic tasks (88 vs 55 on the category index, where 50 is average).
Which is cheaper, Claude Sonnet 4.6 or GPT-5.6 Sol?
Claude Sonnet 4.6 is cheaper: $6.00 against $8.00 per million tokens, blended at three input tokens per output token.
Which is faster, Claude Sonnet 4.6 or GPT-5.6 Sol?
GPT-5.6 Sol streams faster: 59 against 42 output tokens per second.
Which has the larger context window?
Both accept 1M tokens of context.