benchlm.ai

Claude Sonnet 4.6 vs GPT-OSS 20B

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

Quick Verdict

Claude Sonnet 4.6 wins overall with a score of 80 vs 22 (58 point difference).Claude Sonnet 4.6 wins 4 out of 4 categories.

Claude Sonnet 4.6

CreatorAnthropic
TypeProprietary
Context1M
Score80

GPT-OSS 20B

CreatorOpenAI
TypeOpen Weight
Context128K
Score22

Knowledge

Claude Sonnet 4.6

Claude Sonnet 4.6

96

GPT-OSS 20B

28.8

99
MMLU
31
97
GPQA
30
95
SuperGPQA
28
93
OpenBookQA
26

Coding

Claude Sonnet 4.6

Claude Sonnet 4.6

93

GPT-OSS 20B

23

93
HumanEval
23

Mathematics

Claude Sonnet 4.6

Claude Sonnet 4.6

97.1

GPT-OSS 20B

30

99
AIME 2023
31
99
AIME 2024
33
98
AIME 2025
32
95
HMMT Feb 2023
27
97
HMMT Feb 2024
29
96
HMMT Feb 2025
28
96
BRUMO 2025
30

Reasoning

Claude Sonnet 4.6

Claude Sonnet 4.6

94

GPT-OSS 20B

28

95
SimpleQA
29
93
MuSR
27

Frequently Asked Questions

Which is better, Claude Sonnet 4.6 or GPT-OSS 20B?

Claude Sonnet 4.6 scores higher overall with 80 vs 22, a difference of 58 points across all benchmarks.

Which is better for knowledge tasks, Claude Sonnet 4.6 or GPT-OSS 20B?

Claude Sonnet 4.6 leads in knowledge tasks with an average score of 96 vs 28.8.

Which is better for coding, Claude Sonnet 4.6 or GPT-OSS 20B?

Claude Sonnet 4.6 leads in coding with an average score of 93 vs 23.

Which is better for math, Claude Sonnet 4.6 or GPT-OSS 20B?

Claude Sonnet 4.6 leads in math with an average score of 97.1 vs 30.

Which is better for reasoning, Claude Sonnet 4.6 or GPT-OSS 20B?

Claude Sonnet 4.6 leads in reasoning with an average score of 94 vs 28.

Related Comparisons

Claude Sonnet 4.6 vs GPT-5.4Claude Sonnet 4.6 vs Gemini 3.1 ProClaude Sonnet 4.6 vs Claude Opus 4.6Claude Sonnet 4.6 vs GPT-5.3 CodexClaude Sonnet 4.6 vs Grok 4.1Claude Sonnet 4.6 vs GPT-5.2