BenchLeader

GPT-5 vs GPT-5.6 Sol

Verdict
  • GPT-5.6 Sol (high) leads on quality: 68.2 vs 59.9.
  • GPT-5 is stronger in human preference, reasoning.
  • GPT-5.6 Sol (high) is stronger in agents & tools, coding, composite, instruction following, knowledge, long context, multimodal.
  • GPT-5 is 2.3× cheaper ($3.44 vs $8.00 per 1M blended).
MetricGPT-5GPT-5.6 Sol (high)
BenchLeader Index59.968.2
Agents & tools score51.087.9
Coding score61.072.4
Composite score58.082.7
Human preference score61.8
Instruction following score67.767.8
Knowledge score62.273.8
Long context score65.667.4
Multimodal score59.666.4
Reasoning score64.263.3
Blended price $/M$3.44$8.00
Output speed70 tok/s59 tok/s
Time to first answer77.2 s31.0 s
Context window400k1M
Terminal-Bench49.6%
SciCode42.9%56.9%
Remote Labor Index1.7%
WeirdML39.8%88.8%
APEX-Agents18.3%
Epoch Capabilities Index150
LMArena Text1427
LMArena Hard Prompts1449
LMArena Coding1463
LMArena Vision1232
AA Intelligence Index23.042.5
IFBench73.1%69.2%
AA-LCR78.2%81.7%
MMMU-Pro74.2%81.8%
AA-Omniscience-8.720.4
Terminal-Bench Hard32.6%62.1%
GPQA Diamond (AA)85.3%92.8%
Humanity's Last Exam (AA)28.5%46.0%
SciCode (AA)57.8%
τ²-Bench Telecom (AA)84.8%83.3%
PRBench Finance51.3%
PRBench Legal49.0%
EnigmaEval37.1%
VISTA49.7%
MultiNRC52.1%
TutorBench55.3%
Kagi LLM Benchmark72.7%
Aider Polyglot88.0%
SWE-bench Verified (any scaffold)75.6%
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.

GPT-5 vs GPT-5.6 Sol: questions

Is GPT-5 better than GPT-5.6 Sol?
GPT-5.6 Sol (high) leads on quality: 68.2 vs 59.9. 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 GPT-5 better than GPT-5.6 Sol for coding?
GPT-5.6 Sol scores higher in coding (72 vs 61 on the category index, where 50 is average).
Is GPT-5 better than GPT-5.6 Sol for agentic tasks?
GPT-5.6 Sol scores higher in agentic tasks (88 vs 51 on the category index, where 50 is average).
Which is cheaper, GPT-5 or GPT-5.6 Sol?
GPT-5 is cheaper: $3.44 against $8.00 per million tokens, blended at three input tokens per output token.
Which is faster, GPT-5 or GPT-5.6 Sol?
GPT-5 streams faster: 70 against 59 output tokens per second.
Which has the larger context window?
GPT-5.6 Sol accepts more context: 1M against 400k tokens.