GPT-5.1 vs Llama 3.1 405B

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

Quick Verdict

GPT-5.1 wins overall with a score of 76 vs 58 (18 point difference).GPT-5.1 wins 4 out of 4 categories.

Knowledge

GPT-5.1

GPT-5.1

94

Llama 3.1 405B

68.5

97
MMLU
70
95
GPQA
70
93
SuperGPQA
68
91
OpenBookQA
66

Coding

GPT-5.1

GPT-5.1

89

Llama 3.1 405B

62

89
HumanEval
62

Mathematics

GPT-5.1

GPT-5.1

97.1

Llama 3.1 405B

69

99
AIME 2023
70
99
AIME 2024
72
98
AIME 2025
71
95
HMMT Feb 2023
66
97
HMMT Feb 2024
68
96
HMMT Feb 2025
67
96
BRUMO 2025
69

Reasoning

GPT-5.1

GPT-5.1

92

Llama 3.1 405B

67

93
SimpleQA
68
91
MuSR
66

Frequently Asked Questions

Which is better, GPT-5.1 or Llama 3.1 405B?

GPT-5.1 scores higher overall with 76 vs 58, a difference of 18 points across all benchmarks.

Which is better for knowledge tasks, GPT-5.1 or Llama 3.1 405B?

GPT-5.1 leads in knowledge tasks with an average score of 94 vs 68.5.

Which is better for coding, GPT-5.1 or Llama 3.1 405B?

GPT-5.1 leads in coding with an average score of 89 vs 62.

Which is better for math, GPT-5.1 or Llama 3.1 405B?

GPT-5.1 leads in math with an average score of 97.1 vs 69.

Which is better for reasoning, GPT-5.1 or Llama 3.1 405B?

GPT-5.1 leads in reasoning with an average score of 92 vs 67.