benchlm.ai

Claude 3 Opus vs GPT-OSS 20B

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

Quick Verdict

Claude 3 Opus wins overall with a score of 51 vs 22 (29 point difference).Claude 3 Opus wins 4 out of 4 categories.

Claude 3 Opus

CreatorAnthropic
TypeProprietary
Context200K
Score51

GPT-OSS 20B

CreatorOpenAI
TypeOpen Weight
Context128K
Score22

Knowledge

Claude 3 Opus

Claude 3 Opus

59.5

GPT-OSS 20B

28.8

61
MMLU
31
61
GPQA
30
59
SuperGPQA
28
57
OpenBookQA
26

Coding

Claude 3 Opus

Claude 3 Opus

53

GPT-OSS 20B

23

53
HumanEval
23

Mathematics

Claude 3 Opus

Claude 3 Opus

60

GPT-OSS 20B

30

61
AIME 2023
31
63
AIME 2024
33
62
AIME 2025
32
57
HMMT Feb 2023
27
59
HMMT Feb 2024
29
58
HMMT Feb 2025
28
60
BRUMO 2025
30

Reasoning

Claude 3 Opus

Claude 3 Opus

58

GPT-OSS 20B

28

59
SimpleQA
29
57
MuSR
27

Frequently Asked Questions

Which is better, Claude 3 Opus or GPT-OSS 20B?

Claude 3 Opus scores higher overall with 51 vs 22, a difference of 29 points across all benchmarks.

Which is better for knowledge tasks, Claude 3 Opus or GPT-OSS 20B?

Claude 3 Opus leads in knowledge tasks with an average score of 59.5 vs 28.8.

Which is better for coding, Claude 3 Opus or GPT-OSS 20B?

Claude 3 Opus leads in coding with an average score of 53 vs 23.

Which is better for math, Claude 3 Opus or GPT-OSS 20B?

Claude 3 Opus leads in math with an average score of 60 vs 30.

Which is better for reasoning, Claude 3 Opus or GPT-OSS 20B?

Claude 3 Opus leads in reasoning with an average score of 58 vs 28.

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