# GPT-4o vs Mistral Medium 3.5

> Mistral Medium 3.5 is the stronger model overall, scoring 39.6 to 28.5 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-4o-vs-mistral-medium-3-5
- Last updated: 2026-10-10
- Shared benchmarks: 18

## Summary

- They share 18 benchmarks with published results for both. GPT-4o scores higher in 0 categories and Mistral Medium 3.5 in 9 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in math, where Mistral Medium 3.5 leads 36.4 to 10.2.
- Mistral Medium 3.5 is cheaper at $1.50 / $7.50 per million input/output tokens, against $2.50 / $10 for GPT-4o.
- Mistral Medium 3.5 accepts more context: 262K tokens versus 128K.
- Mistral Medium 3.5 has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Noometry Index | 28.5 | 39.6 |
| Rank | 316 | 151 |
| Context | 128K | 262K |
| Input $/M | $2.50 | $1.50 |
| Output $/M | $10 | $7.50 |
| Weights | Proprietary | Open |

## Coding

- GPT-4o: 25.1 (#323)
- Mistral Medium 3.5: 35.7 (#208)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Coding | 1297 | 1461 |
| SWE-bench Verified | 31% | — |
| SWE-bench Verified (bash only) | 21.6% | — |
| Aider Polyglot | 45.3% | — |
| LMArena WebDev | — | 1263 |
| GSO | 0% | — |
| WeirdML | 25.1% | — |
| BigCodeBench Instruct | 51.1% | — |
| LiveBench Coding | 51.4% | — |
| BigCodeBench Complete | 61.1% | — |
| CadEval | 26% | — |
| HumanEval+ | 87.2% | — |
| MBPP+ | 72.2% | — |

## Agentic & Tool Use

- GPT-4o: 20.8 (#133)
- Mistral Medium 3.5: —

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| GDPval | 9.9% | — |
| TheAgentCompany | 8.6% | — |
| Cybench | 12.5% | — |
| BALROG | 32.3% | — |
| LMArena Search | 1006 | — |
| METR Time Horizons | 40.8% | — |

## Reasoning

- GPT-4o: 9.4 (#338)
- Mistral Medium 3.5: 16.6 (#290)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Hard Prompts | 1281 | 1436 |
| Epoch Capabilities Index | 128.97 | 141.42 |
| ARC-AGI-2 | 0% | — |
| SimpleBench | 17.8% | — |
| Kagi LLM Benchmark | — | 41.4% |
| NYT Connections (extended) | — | 12.9% |
| ARC-AGI-1 | 4.5% | — |
| CritPt | 0% | — |
| Chess Puzzles | 13% | — |
| EnigmaEval | 0.8% | — |
| LiveBench Reasoning | 55.8% | — |
| DTBench | 64.5% | — |
| LiveBench Data Analysis | 60.9% | — |
| LMCA | 16.6% | — |
| ForecastBench | 57.7 | — |
| LiveBench | 55.3% | — |

## Math

- GPT-4o: 10.2 (#303)
- Mistral Medium 3.5: 36.4 (#113)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Math | 1285 | 1432 |
| FrontierMath (Tiers 1-3) | 0.4% | — |
| OTIS Mock AIME 2024-2025 | 6.4% | — |
| Omni-MATH | 29.3% | — |
| LiveBench Math | 49.5% | — |
| MATH Level 5 | 53.3% | — |
| FrontierMath (Feb 2025 set) | 0.3% | — |

## Knowledge

- GPT-4o: 28.8 (#235)
- Mistral Medium 3.5: 39.3 (#123)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Expert | 1250 | 1431 |
| GPQA Diamond | 49.2% | — |
| Humanity's Last Exam | 2.7% | — |
| SimpleQA Verified | 26% | — |
| MMLU-Pro | 71.3% | — |
| Confabulations | 15.3% | — |
| Vectara Hallucination Rate | 9.6% | — |
| GPQA (HELM) | 52% | — |
| MMLU | 88.1% | — |

## Multimodal

- GPT-4o: 33.9 (#85)
- Mistral Medium 3.5: 37.6 (#64)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Vision | 1137 | 1222 |
| Video-MME | 71.9% | — |
| GeoBench | 71% | — |
| VPCT | 40% | — |
| ScienceQA | 88.5% | — |

## Multilingual

- GPT-4o: 43.4 (#181)
- Mistral Medium 3.5: 52.1 (#93)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Non-English | 1283 | 1405 |
| LMArena Chinese | 1277 | 1443 |
| LMArena French | 1303 | 1448 |
| LMArena German | 1282 | 1453 |
| LMArena Korean | 1234 | 1387 |
| LMArena Russian | 1286 | 1396 |
| LMArena Spanish | 1292 | 1406 |
| LMArena Japanese | 1257 | — |

## Instruction Following

- GPT-4o: 66.8 (#202)
- Mistral Medium 3.5: 74.7 (#87)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Instruction Following | 1278 | 1414 |
| LiveBench Instruction Following | 68.6% | — |
| IFEval | 81.7% | — |

## Long Context

- GPT-4o: 39.4 (#174)
- Mistral Medium 3.5: 43.2 (#101)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Longer Query | 1289 | 1414 |
| Fiction.LiveBench | 66.7% | — |

## Writing & Preference

- GPT-4o: 52.8 (#160)
- Mistral Medium 3.5: 58.6 (#113)

| Benchmark | GPT-4o | Mistral Medium 3.5 |
|---|---|---|
| LMArena Text | 1300 | 1421 |
| LMArena Creative Writing | 1291 | 1372 |
| LMArena Multi-Turn | 1302 | 1423 |
| Short-Story Creative Writing | 81.8% | — |
| WildBench | 82.8% | — |
| EQ-Bench 4 | — | 993 |
| LiveBench Language | 47.6% | — |

## FAQ

### Is GPT-4o better than Mistral Medium 3.5?

Mistral Medium 3.5 is the stronger model overall, scoring 39.6 to 28.5 on the Noometry Index.

### Which is cheaper, GPT-4o or Mistral Medium 3.5?

Mistral Medium 3.5 is cheaper. It lists at $1.50 per million input tokens and $7.50 per million output tokens; GPT-4o lists at $2.50 and $10.

### Is GPT-4o or Mistral Medium 3.5 better for coding?

Mistral Medium 3.5 scores higher on coding benchmarks: 35.7 versus 25.1 in the Noometry coding category.

### Which has the bigger context window?

Mistral Medium 3.5 does, with 262K tokens against 128K.

### How many benchmarks do GPT-4o and Mistral Medium 3.5 share?

18 benchmarks have published results for both models. GPT-4o has 72 scored results on Noometry and Mistral Medium 3.5 has 22.