BenchLeader

GPT-5.2 vs o3

Verdict
  • GPT-5.2 and o3 are level on quality (61.6 vs 61.6).
  • GPT-5.2 is stronger in composite, human preference, instruction following, knowledge, long context, multimodal.
  • o3 is stronger in agents & tools, coding, reasoning, maths.
  • o3 is 1.4× cheaper ($3.50 vs $4.81 per 1M blended).
  • o3 streams 1.6× faster (107 vs 68 tokens per second).
MetricGPT-5.2o3
BenchLeader Index61.661.6
Agents & tools score61.270.3
Coding score53.762.0
Composite score67.554.5
Human preference score67.862.3
Instruction following score67.465.0
Knowledge score61.158.0
Long context score67.963.8
Multimodal score59.957.9
Reasoning score61.361.5
Maths score78.6
Blended price $/M$4.81$3.50
Output speed68 tok/s107 tok/s
Time to first answer129.4 s6.3 s
Context window400k200k
Humanity's Last Exam27.8%
Terminal-Bench64.9%
SimpleBench45.8%
Remote Labor Index2.1%
APEX-Agents23.0%
Epoch Capabilities Index153.5146.9
LMArena Text14761432
LMArena Hard Prompts14971441
LMArena Coding15151460
LMArena WebDev1417
LMArena Vision12681214
AA Intelligence Index30.420.2
IFBench75.4%71.4%
AA-LCR82.7%74.7%
MMMU-Pro70.1%
AA-Omniscience-0.9-15.6
Terminal-Bench Hard47.0%37.1%
GPQA Diamond (AA)90.3%82.7%
Humanity's Last Exam (AA)37.7%20.1%
τ²-Bench Telecom (AA)84.8%80.7%
SWE-Bench Pro29.9%
PRBench Finance47.7%
PRBench Legal48.6%
VISTA46.6%
MultiNRC42.2%
TutorBench53.5%
MMMU (validation)82.9%
MMMU-Pro (official)76.4%
Kagi LLM Benchmark73.3%67.6%
IFEval (HELM)86.9%
Omni-MATH (HELM)71.4%
WildBench (HELM)86.1%
MMLU-Pro (HELM)85.9%
GPQA Diamond (HELM)75.3%
HELM Capabilities mean81.1%
Aider Polyglot81.3%
SWE-bench Verified (bash only)69.0%58.4%
SWE-bench Verified (any scaffold)58.4%
ARC-AGI-194.5%
ARC-AGI-272.9%
BFCL Overall55.9%63.0%

Data as of 2026-09-12. Best configuration of each model; every score links to its source on the model pages.

GPT-5.2 vs o3: questions

Is GPT-5.2 better than o3?
GPT-5.2 and o3 are level on quality (61.6 vs 61.6). The BenchLeader Index combines every independent quality benchmark; o3 is ahead overall as of 2026-09-12, but check the category scores for your use.
Is GPT-5.2 better than o3 for coding?
o3 scores higher in coding (62 vs 54 on the category index, where 50 is average).
Is GPT-5.2 better than o3 for agentic tasks?
o3 scores higher in agentic tasks (70 vs 61 on the category index, where 50 is average).
Which is cheaper, GPT-5.2 or o3?
o3 is cheaper: $3.50 against $4.81 per million tokens, blended at three input tokens per output token.
Which is faster, GPT-5.2 or o3?
o3 streams faster: 107 against 68 output tokens per second.
Which has the larger context window?
GPT-5.2 accepts more context: 400k against 200k tokens.