benchlm.ai

GPT-OSS 20B 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 22 (49 point difference).o1-preview wins 4 out of 4 categories.

GPT-OSS 20B

CreatorOpenAI
TypeOpen Weight
Context128K
Score22

o1-preview

CreatorOpenAI
TypeProprietary
Context200K
Score71

Knowledge

o1-preview

GPT-OSS 20B

28.8

o1-preview

89

31
MMLU
92
30
GPQA
90
28
SuperGPQA
88
26
OpenBookQA
86

Coding

o1-preview

GPT-OSS 20B

23

o1-preview

86

23
HumanEval
86

Mathematics

o1-preview

GPT-OSS 20B

30

o1-preview

93

31
AIME 2023
94
33
AIME 2024
96
32
AIME 2025
95
27
HMMT Feb 2023
90
29
HMMT Feb 2024
92
28
HMMT Feb 2025
91
30
BRUMO 2025
93

Reasoning

o1-preview

GPT-OSS 20B

28

o1-preview

87

29
SimpleQA
88
27
MuSR
86

Frequently Asked Questions

Which is better, GPT-OSS 20B or o1-preview?

o1-preview scores higher overall with 71 vs 22, a difference of 49 points across all benchmarks.

Which is better for knowledge tasks, GPT-OSS 20B or o1-preview?

o1-preview leads in knowledge tasks with an average score of 89 vs 28.8.

Which is better for coding, GPT-OSS 20B or o1-preview?

o1-preview leads in coding with an average score of 86 vs 23.

Which is better for math, GPT-OSS 20B or o1-preview?

o1-preview leads in math with an average score of 93 vs 30.

Which is better for reasoning, GPT-OSS 20B or o1-preview?

o1-preview leads in reasoning with an average score of 87 vs 28.

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