benchlm.ai

Claude Sonnet 4.5 vs o3-pro

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

Quick Verdict

Claude Sonnet 4.5 wins overall with a score of 74 vs 68 (6 point difference).Claude Sonnet 4.5 wins 4 out of 4 categories.

Claude Sonnet 4.5

CreatorAnthropic
TypeProprietary
Context1M
Score74

o3-pro

CreatorOpenAI
TypeProprietary
Context200K
Score68

Knowledge

Claude Sonnet 4.5

Claude Sonnet 4.5

92

o3-pro

87.3

95
MMLU
88
93
GPQA
89
91
SuperGPQA
87
89
OpenBookQA
85

Coding

Claude Sonnet 4.5

Claude Sonnet 4.5

87

o3-pro

80

87
HumanEval
80

Mathematics

Claude Sonnet 4.5

Claude Sonnet 4.5

96

o3-pro

89

97
AIME 2023
90
99
AIME 2024
92
98
AIME 2025
91
93
HMMT Feb 2023
86
95
HMMT Feb 2024
88
94
HMMT Feb 2025
87
96
BRUMO 2025
89

Reasoning

Claude Sonnet 4.5

Claude Sonnet 4.5

90

o3-pro

85

91
SimpleQA
86
89
MuSR
84

Frequently Asked Questions

Which is better, Claude Sonnet 4.5 or o3-pro?

Claude Sonnet 4.5 scores higher overall with 74 vs 68, a difference of 6 points across all benchmarks.

Which is better for knowledge tasks, Claude Sonnet 4.5 or o3-pro?

Claude Sonnet 4.5 leads in knowledge tasks with an average score of 92 vs 87.3.

Which is better for coding, Claude Sonnet 4.5 or o3-pro?

Claude Sonnet 4.5 leads in coding with an average score of 87 vs 80.

Which is better for math, Claude Sonnet 4.5 or o3-pro?

Claude Sonnet 4.5 leads in math with an average score of 96 vs 89.

Which is better for reasoning, Claude Sonnet 4.5 or o3-pro?

Claude Sonnet 4.5 leads in reasoning with an average score of 90 vs 85.

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