benchlm.ai

Claude 3 Opus vs GPT-OSS 120B

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

Quick Verdict

Claude 3 Opus wins overall with a score of 51 vs 42 (9 point difference).Claude 3 Opus wins 4 out of 4 categories.

Claude 3 Opus

CreatorAnthropic
TypeProprietary
Context200K
Score51

GPT-OSS 120B

CreatorOpenAI
TypeOpen Weight
Context128K
Score42

Knowledge

Claude 3 Opus

Claude 3 Opus

59.5

GPT-OSS 120B

48.8

61
MMLU
51
61
GPQA
50
59
SuperGPQA
48
57
OpenBookQA
46

Coding

Claude 3 Opus

Claude 3 Opus

53

GPT-OSS 120B

43

53
HumanEval
43

Mathematics

Claude 3 Opus

Claude 3 Opus

60

GPT-OSS 120B

50

61
AIME 2023
51
63
AIME 2024
53
62
AIME 2025
52
57
HMMT Feb 2023
47
59
HMMT Feb 2024
49
58
HMMT Feb 2025
48
60
BRUMO 2025
50

Reasoning

Claude 3 Opus

Claude 3 Opus

58

GPT-OSS 120B

48

59
SimpleQA
49
57
MuSR
47

Frequently Asked Questions

Which is better, Claude 3 Opus or GPT-OSS 120B?

Claude 3 Opus scores higher overall with 51 vs 42, a difference of 9 points across all benchmarks.

Which is better for knowledge tasks, Claude 3 Opus or GPT-OSS 120B?

Claude 3 Opus leads in knowledge tasks with an average score of 59.5 vs 48.8.

Which is better for coding, Claude 3 Opus or GPT-OSS 120B?

Claude 3 Opus leads in coding with an average score of 53 vs 43.

Which is better for math, Claude 3 Opus or GPT-OSS 120B?

Claude 3 Opus leads in math with an average score of 60 vs 50.

Which is better for reasoning, Claude 3 Opus or GPT-OSS 120B?

Claude 3 Opus leads in reasoning with an average score of 58 vs 48.

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