benchlm.ai

GPT-5.1 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 76 (1 point difference).GPT-5.1-Codex-Max wins 3 out of 4 categories.

GPT-5.1

CreatorOpenAI
TypeProprietary
Context400K
Score76

GPT-5.1-Codex-Max

CreatorOpenAI
TypeProprietary
Context400K
Score77

Knowledge

GPT-5.1-Codex-Max

GPT-5.1

94

GPT-5.1-Codex-Max

95

97
MMLU
98
95
GPQA
96
93
SuperGPQA
94
91
OpenBookQA
92

Coding

GPT-5.1-Codex-Max

GPT-5.1

89

GPT-5.1-Codex-Max

94

89
HumanEval
94

Mathematics

Tie

GPT-5.1

97.1

GPT-5.1-Codex-Max

97.1

99
AIME 2023
99
99
AIME 2024
99
98
AIME 2025
98
95
HMMT Feb 2023
95
97
HMMT Feb 2024
97
96
HMMT Feb 2025
96
96
BRUMO 2025
96

Reasoning

GPT-5.1-Codex-Max

GPT-5.1

92

GPT-5.1-Codex-Max

93

93
SimpleQA
94
91
MuSR
92

Frequently Asked Questions

Which is better, GPT-5.1 or GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max scores higher overall with 77 vs 76, a difference of 1 points across all benchmarks.

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

GPT-5.1-Codex-Max leads in knowledge tasks with an average score of 95 vs 94.

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

GPT-5.1-Codex-Max leads in coding with an average score of 94 vs 89.

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

GPT-5.1 and GPT-5.1-Codex-Max are tied for math with average scores of 97.1.

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

GPT-5.1-Codex-Max leads in reasoning with an average score of 93 vs 92.

Related Comparisons

GPT-5.1 vs GPT-5.4GPT-5.1 vs Gemini 3.1 ProGPT-5.1 vs Claude Opus 4.6GPT-5.1 vs GPT-5.3 CodexGPT-5.1 vs Grok 4.1GPT-5.1 vs GPT-5.2