GPT-5.1 vs o3

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

Quick Verdict

GPT-5.1 wins overall with a score of 76 vs 67 (9 point difference).GPT-5.1 wins 4 out of 4 categories.

Knowledge

GPT-5.1

GPT-5.1

94

o3

85.3

97
MMLU
86
95
GPQA
87
93
SuperGPQA
85
91
OpenBookQA
83

Coding

GPT-5.1

GPT-5.1

89

o3

78

89
HumanEval
78

Mathematics

GPT-5.1

GPT-5.1

97.1

o3

87

99
AIME 2023
88
99
AIME 2024
90
98
AIME 2025
89
95
HMMT Feb 2023
84
97
HMMT Feb 2024
86
96
HMMT Feb 2025
85
96
BRUMO 2025
87

Reasoning

GPT-5.1

GPT-5.1

92

o3

83

93
SimpleQA
84
91
MuSR
82

Frequently Asked Questions

Which is better, GPT-5.1 or o3?

GPT-5.1 scores higher overall with 76 vs 67, a difference of 9 points across all benchmarks.

Which is better for knowledge tasks, GPT-5.1 or o3?

GPT-5.1 leads in knowledge tasks with an average score of 94 vs 85.3.

Which is better for coding, GPT-5.1 or o3?

GPT-5.1 leads in coding with an average score of 89 vs 78.

Which is better for math, GPT-5.1 or o3?

GPT-5.1 leads in math with an average score of 97.1 vs 87.

Which is better for reasoning, GPT-5.1 or o3?

GPT-5.1 leads in reasoning with an average score of 92 vs 83.