Model comparison

gpt-oss-120b vs Mistral Small

gpt-oss-120b is the stronger model overall, scoring 36.0 to 33.1 on the Noometry Index.

Last verified . 26 shared benchmarks.

gpt-oss-120b OpenAI

36.0

Rank #210 Confirmed

Mistral Small Mistral AI

33.1

Rank #238 Confirmed

Summary

  • They share 26 benchmarks with published results for both. gpt-oss-120b scores higher in 5 categories and Mistral Small in 4 categories; 7 gaps are clear of the uncertainty.
  • The widest gap is in math, where gpt-oss-120b leads 50.6 to 15.4.
  • The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 88.9% for gpt-oss-120b and 5.8% for Mistral Small.
  • gpt-oss-120b is cheaper at $0.037 / $0.17 per million input/output tokens, against $0.15 / $0.60 for Mistral Small.
  • Mistral Small accepts more context: 256K tokens versus 131K.

Side by side

gpt-oss-120b and Mistral Small specifications
gpt-oss-120bMistral Small
ProviderOpenAIMistral AI
Noometry Index36.033.1
Released2025-08-052024-02-26
WeightsOpenOpen
Context window131K256K
Max output41K256K
Input $ / M tokens$0.037$0.15
Output $ / M tokens$0.17$0.60
Results tracked4839

Sponsored placements are available on pages like this one. Advertise on Noometry

Category by category

Coding Too close to call

gpt-oss-120b: 33.2 (#251), Mistral Small: 33.5 (#242)

Coding benchmarks
Benchmarkgpt-oss-120bMistral Small
SciCode36%26.5%
LMArena Coding13801363
ALE-Bench575.62497.62
SWE-bench Verified (bash only)26%—
Aider Polyglot41.8%—
WeirdML48.2%—
BigCodeBench Instruct—36.1%
LiveBench Coding—36.2%
BigCodeBench Complete—46.6%
AlgoTune1.41—

Agentic & Tool Use Mistral Small leads

gpt-oss-120b: 12.1 (#145), Mistral Small: 27.9 (#87)

Agentic & Tool Use benchmarks
Benchmarkgpt-oss-120bMistral Small
Terminal-Bench18.7%—
APEX-Agents4.4%—
Berkeley Function Calling Leaderboard—37.1%
METR Time Horizons56.6%—
Vending-Bench 2-21.53—

Reasoning Too close to call

gpt-oss-120b: 19.5 (#236), Mistral Small: 19.3 (#238)

Reasoning benchmarks
Benchmarkgpt-oss-120bMistral Small
Kagi LLM Benchmark58.6%37.8%
CritPt1.1%0%
LMArena Hard Prompts13641336
DTBench76.3%70.9%
LMCA22.1%20.6%
SimpleBench22.1%—
Chess Puzzles20%—
LiveBench Reasoning—44.8%
Mystery Game Puzzles2%—
LiveBench Data Analysis—53.7%
Surface Evolver Bench25%—
Epoch Capabilities Index139.94—
LiveBench—44%

Math gpt-oss-120b leads

gpt-oss-120b: 50.6 (#43), Mistral Small: 15.4 (#287)

Math benchmarks
Benchmarkgpt-oss-120bMistral Small
OTIS Mock AIME 2024-202588.9%5.8%
LMArena Math13881341
Omni-MATH68.8%—
LiveBench Math—39.9%
MATH Level 5—46.8%

Knowledge gpt-oss-120b leads

gpt-oss-120b: 42.3 (#89), Mistral Small: 30.9 (#214)

Knowledge benchmarks
Benchmarkgpt-oss-120bMistral Small
GPQA Diamond75.8%47.5%
Vectara Hallucination Rate14.2%5.1%
LMArena Expert13561293
MMLU-Pro79.5%—
Confabulations15.7%—
GPQA (HELM)68.4%—
MMLU—68.7%

Multimodal Not comparable

gpt-oss-120b: —, Mistral Small: 32.9 (#91)

Multimodal benchmarks
Benchmarkgpt-oss-120bMistral Small
LMArena Vision—1142

Multilingual gpt-oss-120b leads

gpt-oss-120b: 48.2 (#142), Mistral Small: 45.7 (#164)

Multilingual benchmarks
Benchmarkgpt-oss-120bMistral Small
LMArena Non-English13501315
LMArena Chinese13841342
LMArena French13701337
LMArena German13551341
LMArena Japanese13321275
LMArena Korean12831260
LMArena Russian13431324
LMArena Spanish13881346

Instruction Following gpt-oss-120b leads

gpt-oss-120b: 69.5 (#168), Mistral Small: 66.6 (#204)

Instruction Following benchmarks
Benchmarkgpt-oss-120bMistral Small
LMArena Instruction Following13181310
LiveBench Instruction Following—63.7%
IFEval83.6%—

Long Context Mistral Small leads

gpt-oss-120b: 31.4 (#273), Mistral Small: 40.4 (#151)

Long Context benchmarks
Benchmarkgpt-oss-120bMistral Small
LMArena Longer Query13191327
Fiction.LiveBench44.4%—

Writing & Preference Mistral Small leads

gpt-oss-120b: 46.7 (#213), Mistral Small: 52.6 (#165)

Writing & Preference benchmarks
Benchmarkgpt-oss-120bMistral Small
LMArena Text13661338
LMArena Creative Writing12741304
LMArena Multi-Turn13401344
Short-Story Creative Writing77.1%—
EQ-Bench Creative Writing961—
WildBench84.5%—
LiveBench Language—30.5%

Frequently asked questions

Is gpt-oss-120b better than Mistral Small?

gpt-oss-120b is the stronger model overall, scoring 36.0 to 33.1 on the Noometry Index.

Which is cheaper, gpt-oss-120b or Mistral Small?

gpt-oss-120b is cheaper. It lists at $0.037 per million input tokens and $0.17 per million output tokens; Mistral Small lists at $0.15 and $0.60.

Is gpt-oss-120b or Mistral Small better for coding?

They score almost the same on coding (33.2 vs 33.5); test both on your own repository before choosing.

Which has the bigger context window?

Mistral Small does, with 256K tokens against 131K.

How many benchmarks do gpt-oss-120b and Mistral Small share?

26 benchmarks have published results for both models. gpt-oss-120b has 48 scored results on Noometry and Mistral Small has 39.

Related comparisons

Go deeper