# gpt-oss-20b vs Mistral Large 3

> Mistral Large 3 is the stronger model overall, scoring 38.6 to 32.1 on the Noometry Index. gpt-oss-20b costs 10× less per token, which makes it the better buy when Mistral Large 3's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-oss-20b-vs-mistral-large-3
- Last updated: 2026-10-10
- Shared benchmarks: 18

## Summary

- They share 18 benchmarks with published results for both. gpt-oss-20b scores higher in 3 categories and Mistral Large 3 in 5 categories; 7 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where Mistral Large 3 leads 60.2 to 35.8.
- gpt-oss-20b is cheaper at $0.018 / $0.09 per million input/output tokens, against $0.25 / $0.75 for Mistral Large 3.
- Mistral Large 3 accepts more context: 262K tokens versus 131K.

## Snapshot

| | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Noometry Index | 32.1 | 38.6 |
| Rank | 249 | 172 |
| Context | 131K | 262K |
| Input $/M | $0.018 | $0.25 |
| Output $/M | $0.09 | $0.75 |
| Weights | Open | Open |

## Coding

- gpt-oss-20b: 37.1 (#185)
- Mistral Large 3: 34.1 (#230)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Coding | 1307 | 1447 |
| LMArena WebDev | — | 1230 |
| SciCode | 34.4% | — |
| WeirdML | 40.9% | — |
| ALE-Bench | 566.05 | — |

## Agentic & Tool Use

- gpt-oss-20b: 9.2 (#146)
- Mistral Large 3: —

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| Terminal-Bench | 3.4% | — |

## Reasoning

- gpt-oss-20b: 18.8 (#251)
- Mistral Large 3: 14.6 (#314)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| Kagi LLM Benchmark | 53.2% | 50.9% |
| LMArena Hard Prompts | 1274 | 1429 |
| NYT Connections (extended) | — | 7.5% |
| CritPt | 1.4% | — |
| Chess Puzzles | 4% | — |
| Thematic Generalization | — | 23% |
| DTBench | 68% | — |
| LMCA | 14.5% | — |
| Epoch Capabilities Index | 137.81 | — |

## Math

- gpt-oss-20b: 37.6 (#93)
- Mistral Large 3: 36.0 (#131)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Math | 1317 | 1415 |
| OTIS Mock AIME 2024-2025 | 65.3% | — |
| Omni-MATH | 56.5% | — |

## Knowledge

- gpt-oss-20b: 34.6 (#186)
- Mistral Large 3: 35.5 (#173)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Expert | 1258 | 1421 |
| GPQA Diamond | 60.8% | — |
| MMLU-Pro | 74% | — |
| Vectara Hallucination Rate | — | 14.5% |
| GPQA (HELM) | 59.4% | — |

## Multimodal

- gpt-oss-20b: —
- Mistral Large 3: 37.6 (#65)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Vision | — | 1222 |

## Multilingual

- gpt-oss-20b: 42.4 (#192)
- Mistral Large 3: 52.6 (#79)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Non-English | 1269 | 1412 |
| LMArena Chinese | 1311 | 1448 |
| LMArena German | 1249 | 1438 |
| LMArena Japanese | 1245 | 1399 |
| LMArena Korean | 1239 | 1384 |
| LMArena Russian | 1279 | 1412 |
| LMArena Spanish | 1267 | 1437 |
| LMArena French | — | 1456 |

## Instruction Following

- gpt-oss-20b: 62.0 (#235)
- Mistral Large 3: 74.1 (#104)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Instruction Following | 1236 | 1402 |
| IFEval | 73.2% | — |

## Long Context

- gpt-oss-20b: 37.9 (#203)
- Mistral Large 3: 43.1 (#102)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Longer Query | 1251 | 1413 |

## Writing & Preference

- gpt-oss-20b: 35.8 (#260)
- Mistral Large 3: 60.2 (#100)

| Benchmark | gpt-oss-20b | Mistral Large 3 |
|---|---|---|
| LMArena Text | 1288 | 1427 |
| LMArena Creative Writing | 1201 | 1385 |
| EQ-Bench Creative Writing | 666 | 1412 |
| LMArena Multi-Turn | 1268 | 1429 |
| WildBench | 73.7% | — |

## FAQ

### Is gpt-oss-20b better than Mistral Large 3?

Mistral Large 3 is the stronger model overall, scoring 38.6 to 32.1 on the Noometry Index. gpt-oss-20b costs 10× less per token, which makes it the better buy when Mistral Large 3's lead doesn't matter for your workload.

### Which is cheaper, gpt-oss-20b or Mistral Large 3?

gpt-oss-20b is cheaper. It lists at $0.018 per million input tokens and $0.09 per million output tokens; Mistral Large 3 lists at $0.25 and $0.75.

### Is gpt-oss-20b or Mistral Large 3 better for coding?

gpt-oss-20b scores higher on coding benchmarks: 37.1 versus 34.1 in the Noometry coding category.

### Which has the bigger context window?

Mistral Large 3 does, with 262K tokens against 131K.

### How many benchmarks do gpt-oss-20b and Mistral Large 3 share?

18 benchmarks have published results for both models. gpt-oss-20b has 34 scored results on Noometry and Mistral Large 3 has 24.