GPT-4o vs GPT-OSS 120B

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

Quick Verdict

GPT-4o wins overall with a score of 56 vs 42 (14 point difference).GPT-4o wins 4 out of 4 categories.

Knowledge

GPT-4o

GPT-4o

64.5

GPT-OSS 120B

48.8

66
MMLU
51
66
GPQA
50
64
SuperGPQA
48
62
OpenBookQA
46

Coding

GPT-4o

GPT-4o

58

GPT-OSS 120B

43

58
HumanEval
43

Mathematics

GPT-4o

GPT-4o

65

GPT-OSS 120B

50

66
AIME 2023
51
68
AIME 2024
53
67
AIME 2025
52
62
HMMT Feb 2023
47
64
HMMT Feb 2024
49
63
HMMT Feb 2025
48
65
BRUMO 2025
50

Reasoning

GPT-4o

GPT-4o

63

GPT-OSS 120B

48

64
SimpleQA
49
62
MuSR
47

Frequently Asked Questions

Which is better, GPT-4o or GPT-OSS 120B?

GPT-4o scores higher overall with 56 vs 42, a difference of 14 points across all benchmarks.

Which is better for knowledge tasks, GPT-4o or GPT-OSS 120B?

GPT-4o leads in knowledge tasks with an average score of 64.5 vs 48.8.

Which is better for coding, GPT-4o or GPT-OSS 120B?

GPT-4o leads in coding with an average score of 58 vs 43.

Which is better for math, GPT-4o or GPT-OSS 120B?

GPT-4o leads in math with an average score of 65 vs 50.

Which is better for reasoning, GPT-4o or GPT-OSS 120B?

GPT-4o leads in reasoning with an average score of 63 vs 48.