Model comparison

GPT-5.1 vs o3-pro

GPT-5.1 is the stronger model overall, scoring 49.0 to 42.9 on the Noometry Index.

Last verified . 7 shared benchmarks.

GPT-5.1 OpenAI

49.0

Rank #53 Confirmed

o3-pro OpenAI

42.9

Rank #105 Confirmed

Summary

  • They share 7 benchmarks with published results for both. GPT-5.1 scores higher in 3 categories and o3-pro in 2 categories; 5 gaps are clear of the uncertainty.
  • The widest gap is in long context, where o3-pro leads 72.2 to 47.6.
  • The biggest single-benchmark swing is ARC-AGI-1: 72.8% for GPT-5.1 and 59.3% for o3-pro.
  • GPT-5.1 is cheaper at $1.25 / $10 per million input/output tokens, against $20 / $80 for o3-pro.
  • GPT-5.1 accepts more context: 400K tokens versus 200K.

Side by side

GPT-5.1 and o3-pro specifications
GPT-5.1o3-pro
ProviderOpenAIOpenAI
Noometry Index49.042.9
Released2025-11-132025-06-10
WeightsProprietaryProprietary
Context window400K200K
Max output128K100K
Input $ / M tokens$1.25$20
Output $ / M tokens$10$80
Results tracked6312

Sponsored placements are available on pages like this one. Advertise on Noometry

Category by category

Coding o3-pro leads

GPT-5.1: 46.4 (#66), o3-pro: 55.5 (#24)

Coding benchmarks
BenchmarkGPT-5.1o3-pro
WeirdML60.8%58.2%
SWE-bench Verified68%—
SWE-bench Verified (bash only)66%—
Aider Polyglot—84.9%
LMArena WebDev1395—
SciCode43.3%—
GSO13.7%—
LiveBench Coding72.5%—
LMArena Coding1454—
ALE-Bench1,192—

Agentic & Tool Use Not comparable

GPT-5.1: 32.7 (#60), o3-pro: —

Agentic & Tool Use benchmarks
BenchmarkGPT-5.1o3-pro
Terminal-Bench47.6%—
DeepResearch Bench42.8%—
LMArena Search1199—
Vending-Bench 21,473—

Reasoning GPT-5.1 leads

GPT-5.1: 39.8 (#58), o3-pro: 23.8 (#171)

Reasoning benchmarks
BenchmarkGPT-5.1o3-pro
ARC-AGI-217.6%4.9%
ARC-AGI-172.8%59.3%
DTBench90.1%86.9%
LMCA43.9%38.5%
Epoch Capabilities Index149.64147.42
SimpleBench53.2%—
Kagi LLM Benchmark—72.1%
CritPt4.9%—
Chess Puzzles32%—
EnigmaEval11.2%—
LiveBench Reasoning95.8%—
LMArena Hard Prompts1457—
Mystery Game Puzzles19%—
LiveBench Data Analysis72.1%—
ForecastBench58.1—
LiveBench78.8%—

Math Not comparable

GPT-5.1: 52.2 (#51), o3-pro: —

Math benchmarks
BenchmarkGPT-5.1o3-pro
OTIS Mock AIME 2024-202588.6%—
Omni-MATH46.4%—
LiveBench Math94.5%—
LMArena Math1447—
FrontierMath (Feb 2025 set)31%—
FrontierMath Tier 4 (v1)12.5%—

Knowledge GPT-5.1 leads

GPT-5.1: 50.6 (#71), o3-pro: 29.5 (#238)

Knowledge benchmarks
BenchmarkGPT-5.1o3-pro
Vectara Hallucination Rate10.9%23.3%
GPQA Diamond87.6%—
Humanity's Last Exam23.7%—
SimpleQA Verified48%—
MMLU-Pro57.9%—
Confabulations—14.2%
GPQA (HELM)44.2%—
LMArena Expert1470—

Multimodal Not comparable

GPT-5.1: 44.8 (#19), o3-pro: —

Multimodal benchmarks
BenchmarkGPT-5.1o3-pro
LMArena Vision1250—
VPCT58.7%—
LMArena Document1403—

Multilingual Not comparable

GPT-5.1: 53.8 (#56), o3-pro: —

Multilingual benchmarks
BenchmarkGPT-5.1o3-pro
LMArena Non-English1431—
LMArena Chinese1495—
LMArena French1450—
LMArena German1438—
LMArena Japanese1453—
LMArena Korean1401—
LMArena Russian1435—
LMArena Spanish1433—

Instruction Following Not comparable

GPT-5.1: 83.9 (#1), o3-pro: —

Instruction Following benchmarks
BenchmarkGPT-5.1o3-pro
LiveBench Instruction Following93.3%—
IFEval93.5%—
LMArena Instruction Following1443—

Long Context o3-pro leads

GPT-5.1: 47.6 (#14), o3-pro: 72.2 (#1)

Long Context benchmarks
BenchmarkGPT-5.1o3-pro
Fiction.LiveBench—97.2%
CL-bench23.7%—
CL-bench Life17.3%—
LMArena Longer Query1447—

Writing & Preference GPT-5.1 leads

GPT-5.1: 64.5 (#55), o3-pro: 57.1 (#133)

Writing & Preference benchmarks
BenchmarkGPT-5.1o3-pro
LMArena Text1443—
LMArena Creative Writing1427—
Short-Story Creative Writing—84.4%
WildBench86.3%—
LMArena Multi-Turn1450—
LiveBench Language80.2%—

Frequently asked questions

Is GPT-5.1 better than o3-pro?

GPT-5.1 is the stronger model overall, scoring 49.0 to 42.9 on the Noometry Index.

Which is cheaper, GPT-5.1 or o3-pro?

GPT-5.1 is cheaper. It lists at $1.25 per million input tokens and $10 per million output tokens; o3-pro lists at $20 and $80.

Is GPT-5.1 or o3-pro better for coding?

o3-pro scores higher on coding benchmarks: 55.5 versus 46.4 in the Noometry coding category.

Which has the bigger context window?

GPT-5.1 does, with 400K tokens against 200K.

How many benchmarks do GPT-5.1 and o3-pro share?

7 benchmarks have published results for both models. GPT-5.1 has 63 scored results on Noometry and o3-pro has 12.

Related comparisons

Go deeper