DeepSeek V3.1 (Reasoning) vs GPT-OSS 120B

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

Quick Verdict

GPT-OSS 120B wins overall with a score of 42 vs 25 (17 point difference).GPT-OSS 120B wins 4 out of 4 categories.

Knowledge

GPT-OSS 120B

DeepSeek V3.1 (Reasoning)

31.8

GPT-OSS 120B

48.8

34
MMLU
51
33
GPQA
50
31
SuperGPQA
48
29
OpenBookQA
46

Coding

GPT-OSS 120B

DeepSeek V3.1 (Reasoning)

26

GPT-OSS 120B

43

26
HumanEval
43

Mathematics

GPT-OSS 120B

DeepSeek V3.1 (Reasoning)

33

GPT-OSS 120B

50

34
AIME 2023
51
36
AIME 2024
53
35
AIME 2025
52
30
HMMT Feb 2023
47
32
HMMT Feb 2024
49
31
HMMT Feb 2025
48
33
BRUMO 2025
50

Reasoning

GPT-OSS 120B

DeepSeek V3.1 (Reasoning)

31

GPT-OSS 120B

48

32
SimpleQA
49
30
MuSR
47

Frequently Asked Questions

Which is better, DeepSeek V3.1 (Reasoning) or GPT-OSS 120B?

GPT-OSS 120B scores higher overall with 42 vs 25, a difference of 17 points across all benchmarks.

Which is better for knowledge tasks, DeepSeek V3.1 (Reasoning) or GPT-OSS 120B?

GPT-OSS 120B leads in knowledge tasks with an average score of 48.8 vs 31.8.

Which is better for coding, DeepSeek V3.1 (Reasoning) or GPT-OSS 120B?

GPT-OSS 120B leads in coding with an average score of 43 vs 26.

Which is better for math, DeepSeek V3.1 (Reasoning) or GPT-OSS 120B?

GPT-OSS 120B leads in math with an average score of 50 vs 33.

Which is better for reasoning, DeepSeek V3.1 (Reasoning) or GPT-OSS 120B?

GPT-OSS 120B leads in reasoning with an average score of 48 vs 31.