benchlm.ai

GPT-OSS 120B vs o1-preview

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

Quick Verdict

o1-preview wins overall with a score of 71 vs 42 (29 point difference).o1-preview wins 4 out of 4 categories.

GPT-OSS 120B

CreatorOpenAI
TypeOpen Weight
Context128K
Score42

o1-preview

CreatorOpenAI
TypeProprietary
Context200K
Score71

Knowledge

o1-preview

GPT-OSS 120B

48.8

o1-preview

89

51
MMLU
92
50
GPQA
90
48
SuperGPQA
88
46
OpenBookQA
86

Coding

o1-preview

GPT-OSS 120B

43

o1-preview

86

43
HumanEval
86

Mathematics

o1-preview

GPT-OSS 120B

50

o1-preview

93

51
AIME 2023
94
53
AIME 2024
96
52
AIME 2025
95
47
HMMT Feb 2023
90
49
HMMT Feb 2024
92
48
HMMT Feb 2025
91
50
BRUMO 2025
93

Reasoning

o1-preview

GPT-OSS 120B

48

o1-preview

87

49
SimpleQA
88
47
MuSR
86

Frequently Asked Questions

Which is better, GPT-OSS 120B or o1-preview?

o1-preview scores higher overall with 71 vs 42, a difference of 29 points across all benchmarks.

Which is better for knowledge tasks, GPT-OSS 120B or o1-preview?

o1-preview leads in knowledge tasks with an average score of 89 vs 48.8.

Which is better for coding, GPT-OSS 120B or o1-preview?

o1-preview leads in coding with an average score of 86 vs 43.

Which is better for math, GPT-OSS 120B or o1-preview?

o1-preview leads in math with an average score of 93 vs 50.

Which is better for reasoning, GPT-OSS 120B or o1-preview?

o1-preview leads in reasoning with an average score of 87 vs 48.

Related Comparisons

GPT-OSS 120B vs GPT-5.4GPT-OSS 120B vs Gemini 3.1 ProGPT-OSS 120B vs Claude Opus 4.6GPT-OSS 120B vs GPT-5.3 CodexGPT-OSS 120B vs Grok 4.1GPT-OSS 120B vs GPT-5.2