Noometry

Model comparison

Claude 3 Opus vs GPT-5.1-Codex

GPT-5.1-Codex is the stronger model overall, scoring 38.6 to 29.5 on the Noometry Index.

Last verified . 1 shared benchmarks.

Claude 3 Opus Anthropic

29.5

Rank #310 Confirmed

GPT-5.1-Codex OpenAI

38.6

Rank #186 Reported

Summary

  • They share 1 benchmark with published results for both. Claude 3 Opus scores higher in 0 categories and GPT-5.1-Codex in 3 categories; 3 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-5.1-Codex leads 30.3 to 14.8.

Side by side

Claude 3 OpusGPT-5.1-Codex
ProviderAnthropicOpenAI
Noometry Index29.538.6
Released2024-02-292025-11-12
WeightsProprietaryProprietary
Context window—400K
Max output—128K
Input $ / M tokens—$1.25
Output $ / M tokens—$10
Results tracked466

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

Category by category

Coding GPT-5.1-Codex leads

Claude 3 Opus: 32.9 (#267), GPT-5.1-Codex: 41.9 (#116)

BenchmarkClaude 3 OpusGPT-5.1-Codex
SWE-bench Verified (bash only)—66%
LMArena WebDev—1337
WeirdML19.2%—
BigCodeBench Instruct45.5%—
LiveBench Coding38.6%—
LMArena Coding1264—
BigCodeBench Complete57.4%—
ALE-Bench—1,245
HumanEval+77.4%—
MBPP+73.3%—

Agentic & Tool Use GPT-5.1-Codex leads

Claude 3 Opus: 24.6 (#116), GPT-5.1-Codex: 38.0 (#33)

BenchmarkClaude 3 OpusGPT-5.1-Codex
METR Time Horizons29.5%70.8%
Terminal-Bench—60.4%
Cybench10%—

Reasoning Not comparable

Claude 3 Opus: 14.6 (#324), GPT-5.1-Codex: —

BenchmarkClaude 3 OpusGPT-5.1-Codex
SimpleBench23.5%—
Chess Puzzles5%—
EnigmaEval0.8%—
LiveBench Reasoning40.6%—
LMArena Hard Prompts1245—
DTBench61.6%—
LiveBench Data Analysis57.9%—
LMCA17%—
Epoch Capabilities Index126.91—
ForecastBench58.4—
LiveBench49.2%—
WinoGrande88.5%—

Math GPT-5.1-Codex leads

Claude 3 Opus: 14.8 (#299), GPT-5.1-Codex: 30.3 (#235)

BenchmarkClaude 3 OpusGPT-5.1-Codex
OTIS Mock AIME 2024-20254.7%—
ProofBench—9%
LiveBench Math43.6%—
LMArena Math1273—
MATH Level 537.5%—

Knowledge Not comparable

Claude 3 Opus: 24.5 (#267), GPT-5.1-Codex: —

BenchmarkClaude 3 OpusGPT-5.1-Codex
GPQA Diamond47.2%—
SimpleQA Verified12.6%—
Confabulations22.7%—
LMArena Expert1223—
MMLU84.6%—

Multimodal Not comparable

Claude 3 Opus: 27.1 (#116), GPT-5.1-Codex: —

BenchmarkClaude 3 OpusGPT-5.1-Codex
LMArena Vision1023—

Multilingual Not comparable

Claude 3 Opus: 41.4 (#207), GPT-5.1-Codex: —

BenchmarkClaude 3 OpusGPT-5.1-Codex
LMArena Non-English1258—
LMArena Chinese1248—
LMArena French1275—
LMArena German1258—
LMArena Japanese1204—
LMArena Korean1187—
LMArena Russian1280—
LMArena Spanish1246—

Instruction Following Not comparable

Claude 3 Opus: 64.1 (#228), GPT-5.1-Codex: —

BenchmarkClaude 3 OpusGPT-5.1-Codex
LiveBench Instruction Following63.9%—
LMArena Instruction Following1248—

Long Context Not comparable

Claude 3 Opus: 38.2 (#202), GPT-5.1-Codex: —

BenchmarkClaude 3 OpusGPT-5.1-Codex
LMArena Longer Query1259—

Writing & Preference Not comparable

Claude 3 Opus: 47.2 (#213), GPT-5.1-Codex: —

BenchmarkClaude 3 OpusGPT-5.1-Codex
LMArena Text1262—
LMArena Creative Writing1235—
LMArena Multi-Turn1275—
LiveBench Language50.4%—

Frequently asked questions

Is Claude 3 Opus better than GPT-5.1-Codex?

GPT-5.1-Codex is the stronger model overall, scoring 38.6 to 29.5 on the Noometry Index.

Is Claude 3 Opus or GPT-5.1-Codex better for coding?

GPT-5.1-Codex scores higher on coding benchmarks: 41.9 versus 32.9 in the Noometry coding category.

How many benchmarks do Claude 3 Opus and GPT-5.1-Codex share?

1 benchmark has published results for both models. Claude 3 Opus has 46 scored results on Noometry and GPT-5.1-Codex has 6.

Related comparisons

Go deeper