benchlm.ai

GPT-5.1-Codex-Max vs Qwen3.5 397B

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 65 (12 point difference).GPT-5.1-Codex-Max wins 4 out of 4 categories.

GPT-5.1-Codex-Max

CreatorOpenAI
TypeProprietary
Context400K
Score77

Qwen3.5 397B

CreatorAlibaba
TypeOpen Weight
Context128K
Score65

Knowledge

GPT-5.1-Codex-Max

GPT-5.1-Codex-Max

95

Qwen3.5 397B

80.8

98
MMLU
83
96
GPQA
82
94
SuperGPQA
80
92
OpenBookQA
78

Coding

GPT-5.1-Codex-Max

GPT-5.1-Codex-Max

94

Qwen3.5 397B

75

94
HumanEval
75

Mathematics

GPT-5.1-Codex-Max

GPT-5.1-Codex-Max

97.1

Qwen3.5 397B

82

99
AIME 2023
83
99
AIME 2024
85
98
AIME 2025
84
95
HMMT Feb 2023
79
97
HMMT Feb 2024
81
96
HMMT Feb 2025
80
96
BRUMO 2025
82

Reasoning

GPT-5.1-Codex-Max

GPT-5.1-Codex-Max

93

Qwen3.5 397B

79

94
SimpleQA
80
92
MuSR
78

Frequently Asked Questions

Which is better, GPT-5.1-Codex-Max or Qwen3.5 397B?

GPT-5.1-Codex-Max scores higher overall with 77 vs 65, a difference of 12 points across all benchmarks.

Which is better for knowledge tasks, GPT-5.1-Codex-Max or Qwen3.5 397B?

GPT-5.1-Codex-Max leads in knowledge tasks with an average score of 95 vs 80.8.

Which is better for coding, GPT-5.1-Codex-Max or Qwen3.5 397B?

GPT-5.1-Codex-Max leads in coding with an average score of 94 vs 75.

Which is better for math, GPT-5.1-Codex-Max or Qwen3.5 397B?

GPT-5.1-Codex-Max leads in math with an average score of 97.1 vs 82.

Which is better for reasoning, GPT-5.1-Codex-Max or Qwen3.5 397B?

GPT-5.1-Codex-Max leads in reasoning with an average score of 93 vs 79.

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