Gemini 2.5 Flash vs o3

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

Quick Verdict

o3 wins overall with a score of 67 vs 41 (26 point difference).o3 wins 4 out of 4 categories.

Knowledge

o3

Gemini 2.5 Flash

47.8

o3

85.3

50
MMLU
86
49
GPQA
87
47
SuperGPQA
85
45
OpenBookQA
83

Coding

o3

Gemini 2.5 Flash

42

o3

78

42
HumanEval
78

Mathematics

o3

Gemini 2.5 Flash

49

o3

87

50
AIME 2023
88
52
AIME 2024
90
51
AIME 2025
89
46
HMMT Feb 2023
84
48
HMMT Feb 2024
86
47
HMMT Feb 2025
85
49
BRUMO 2025
87

Reasoning

o3

Gemini 2.5 Flash

47

o3

83

48
SimpleQA
84
46
MuSR
82

Frequently Asked Questions

Which is better, Gemini 2.5 Flash or o3?

o3 scores higher overall with 67 vs 41, a difference of 26 points across all benchmarks.

Which is better for knowledge tasks, Gemini 2.5 Flash or o3?

o3 leads in knowledge tasks with an average score of 85.3 vs 47.8.

Which is better for coding, Gemini 2.5 Flash or o3?

o3 leads in coding with an average score of 78 vs 42.

Which is better for math, Gemini 2.5 Flash or o3?

o3 leads in math with an average score of 87 vs 49.

Which is better for reasoning, Gemini 2.5 Flash or o3?

o3 leads in reasoning with an average score of 83 vs 47.