benchlm.ai

Claude 3 Opus vs GPT-5.1-Codex-Max

Side-by-side benchmark comparison across knowledge, coding, math, and reasoning.

Quick Verdict

GPT-5.1-Codex-Max wins overall with a score of 77 vs 51 (26 point difference).GPT-5.1-Codex-Max wins 4 out of 4 categories.

Claude 3 Opus

CreatorAnthropic
TypeProprietary
Context200K
Score51

GPT-5.1-Codex-Max

CreatorOpenAI
TypeProprietary
Context400K
Score77

Knowledge

GPT-5.1-Codex-Max

Claude 3 Opus

59.5

GPT-5.1-Codex-Max

95

61
MMLU
98
61
GPQA
96
59
SuperGPQA
94
57
OpenBookQA
92

Coding

GPT-5.1-Codex-Max

Claude 3 Opus

53

GPT-5.1-Codex-Max

94

53
HumanEval
94

Mathematics

GPT-5.1-Codex-Max

Claude 3 Opus

60

GPT-5.1-Codex-Max

97.1

61
AIME 2023
99
63
AIME 2024
99
62
AIME 2025
98
57
HMMT Feb 2023
95
59
HMMT Feb 2024
97
58
HMMT Feb 2025
96
60
BRUMO 2025
96

Reasoning

GPT-5.1-Codex-Max

Claude 3 Opus

58

GPT-5.1-Codex-Max

93

59
SimpleQA
94
57
MuSR
92

Frequently Asked Questions

Which is better, Claude 3 Opus or GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max scores higher overall with 77 vs 51, a difference of 26 points across all benchmarks.

Which is better for knowledge tasks, Claude 3 Opus or GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max leads in knowledge tasks with an average score of 95 vs 59.5.

Which is better for coding, Claude 3 Opus or GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max leads in coding with an average score of 94 vs 53.

Which is better for math, Claude 3 Opus or GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max leads in math with an average score of 97.1 vs 60.

Which is better for reasoning, Claude 3 Opus or GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max leads in reasoning with an average score of 93 vs 58.

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Claude 3 Opus vs GPT-5.4Claude 3 Opus vs Gemini 3.1 ProClaude 3 Opus vs Claude Opus 4.6Claude 3 Opus vs GPT-5.3 CodexClaude 3 Opus vs Grok 4.1Claude 3 Opus vs GPT-5.2