# Mistral Medium 3.1 vs Step 3.5 Flash

> Step 3.5 Flash is the stronger model overall, scoring 41.7 to 31.5 on the Noometry Index.

- Canonical page: https://noometry.com/compare/mistral-medium-3-1-vs-step-3-5-flash
- Last updated: 2026-10-10
- Shared benchmarks: 1

## Summary

- They share 1 benchmark with published results for both. Mistral Medium 3.1 scores higher in 0 categories and Step 3.5 Flash in 2 categories; 2 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Step 3.5 Flash leads 21.2 to 10.1.
- The biggest single-benchmark swing is NYT Connections (extended): 6.5% for Mistral Medium 3.1 and 28.4% for Step 3.5 Flash.
- Step 3.5 Flash is cheaper at $0.10 / $0.30 per million input/output tokens, against $0.40 / $2 for Mistral Medium 3.1.
- Step 3.5 Flash accepts more context: 256K tokens versus 131K.
- Step 3.5 Flash has downloadable open weights; the other is API-only.

## Snapshot

| | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| Provider | Mistral AI | StepFun |
| Noometry Index | 31.5 | 41.7 |
| Rank | 260 | 116 |
| Context | 131K | 256K |
| Input $/M | $0.40 | $0.10 |
| Output $/M | $2 | $0.30 |
| Weights | Proprietary | Open |

## Coding

- Mistral Medium 3.1: —
- Step 3.5 Flash: 41.7 (#106)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| LMArena Coding | — | 1436 |

## Reasoning

- Mistral Medium 3.1: 10.1 (#336)
- Step 3.5 Flash: 21.2 (#202)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| NYT Connections (extended) | 6.5% | 28.4% |
| Thematic Generalization | 20.3% | — |
| LMArena Hard Prompts | — | 1411 |

## Math

- Mistral Medium 3.1: —
- Step 3.5 Flash: 40.6 (#77)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| MathArena Final-Answer Competitions | — | 66.8% |
| LMArena Math | — | 1408 |

## Knowledge

- Mistral Medium 3.1: —
- Step 3.5 Flash: 39.0 (#127)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| LMArena Expert | — | 1422 |

## Multilingual

- Mistral Medium 3.1: —
- Step 3.5 Flash: 50.7 (#115)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| LMArena Non-English | — | 1386 |
| LMArena Chinese | — | 1448 |
| LMArena French | — | 1421 |
| LMArena German | — | 1404 |
| LMArena Japanese | — | 1353 |
| LMArena Korean | — | 1350 |
| LMArena Russian | — | 1385 |
| LMArena Spanish | — | 1419 |

## Instruction Following

- Mistral Medium 3.1: —
- Step 3.5 Flash: 73.3 (#119)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| LMArena Instruction Following | — | 1385 |

## Long Context

- Mistral Medium 3.1: —
- Step 3.5 Flash: 42.8 (#112)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| LMArena Longer Query | — | 1402 |

## Writing & Preference

- Mistral Medium 3.1: 55.6 (#140)
- Step 3.5 Flash: 59.0 (#108)

| Benchmark | Mistral Medium 3.1 | Step 3.5 Flash |
|---|---|---|
| LMArena Text | — | 1403 |
| LMArena Creative Writing | — | 1357 |
| EQ-Bench Creative Writing | 1476 | — |
| LMArena Multi-Turn | — | 1405 |

## FAQ

### Is Mistral Medium 3.1 better than Step 3.5 Flash?

Step 3.5 Flash is the stronger model overall, scoring 41.7 to 31.5 on the Noometry Index.

### Which is cheaper, Mistral Medium 3.1 or Step 3.5 Flash?

Step 3.5 Flash is cheaper. It lists at $0.10 per million input tokens and $0.30 per million output tokens; Mistral Medium 3.1 lists at $0.40 and $2.

### Which has the bigger context window?

Step 3.5 Flash does, with 256K tokens against 131K.

### How many benchmarks do Mistral Medium 3.1 and Step 3.5 Flash share?

1 benchmark has published results for both models. Mistral Medium 3.1 has 3 scored results on Noometry and Step 3.5 Flash has 19.