benchlm.ai

GPT-OSS 20B vs Nemotron Ultra 253B

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

Quick Verdict

Nemotron Ultra 253B wins overall with a score of 40 vs 22 (18 point difference).Nemotron Ultra 253B wins 4 out of 4 categories.

GPT-OSS 20B

CreatorOpenAI
TypeOpen Weight
Context128K
Score22

Nemotron Ultra 253B

CreatorNVIDIA
TypeOpen Weight
Context32K
Score40

Knowledge

Nemotron Ultra 253B

GPT-OSS 20B

28.8

Nemotron Ultra 253B

46.8

31
MMLU
49
30
GPQA
48
28
SuperGPQA
46
26
OpenBookQA
44

Coding

Nemotron Ultra 253B

GPT-OSS 20B

23

Nemotron Ultra 253B

41

23
HumanEval
41

Mathematics

Nemotron Ultra 253B

GPT-OSS 20B

30

Nemotron Ultra 253B

48

31
AIME 2023
49
33
AIME 2024
51
32
AIME 2025
50
27
HMMT Feb 2023
45
29
HMMT Feb 2024
47
28
HMMT Feb 2025
46
30
BRUMO 2025
48

Reasoning

Nemotron Ultra 253B

GPT-OSS 20B

28

Nemotron Ultra 253B

46

29
SimpleQA
47
27
MuSR
45

Frequently Asked Questions

Which is better, GPT-OSS 20B or Nemotron Ultra 253B?

Nemotron Ultra 253B scores higher overall with 40 vs 22, a difference of 18 points across all benchmarks.

Which is better for knowledge tasks, GPT-OSS 20B or Nemotron Ultra 253B?

Nemotron Ultra 253B leads in knowledge tasks with an average score of 46.8 vs 28.8.

Which is better for coding, GPT-OSS 20B or Nemotron Ultra 253B?

Nemotron Ultra 253B leads in coding with an average score of 41 vs 23.

Which is better for math, GPT-OSS 20B or Nemotron Ultra 253B?

Nemotron Ultra 253B leads in math with an average score of 48 vs 30.

Which is better for reasoning, GPT-OSS 20B or Nemotron Ultra 253B?

Nemotron Ultra 253B leads in reasoning with an average score of 46 vs 28.

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