# Mercury 2 vs Mistral Small 3.1

> Mercury 2 is the stronger model overall, scoring 38.8 to 31.4 on the Noometry Index.

- Canonical page: https://noometry.com/compare/mercury-2-vs-mistral-small-3-1
- Last updated: 2026-10-10
- Shared benchmarks: 11

## Summary

- They share 11 benchmarks with published results for both. Mercury 2 scores higher in 6 categories and Mistral Small 3.1 in 1 category; 6 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where Mercury 2 leads 54.0 to 37.2.
- Mercury 2 is cheaper at $0.25 / $0.75 per million input/output tokens, against $0.35 / $0.56 for Mistral Small 3.1.
- Mistral Small 3.1 has downloadable open weights; the other is API-only.

## Snapshot

| | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| Provider | Inception | Mistral AI |
| Noometry Index | 38.8 | 31.4 |
| Rank | 167 | 263 |
| Context | 128K | 128K |
| Input $/M | $0.25 | $0.35 |
| Output $/M | $0.75 | $0.56 |
| Weights | Proprietary | Open |

## Coding

- Mercury 2: 33.2 (#250)
- Mistral Small 3.1: 37.7 (#175)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Coding | 1391 | 1309 |
| LMArena WebDev | 1170 | — |
| SciCode | 38.7% | — |
| WeirdML | 43.2% | — |
| ALE-Bench | 785.58 | — |

## Reasoning

- Mercury 2: 23.0 (#170)
- Mistral Small 3.1: 18.9 (#249)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Hard Prompts | 1362 | 1278 |
| CritPt | 0.8% | — |
| Chess Puzzles | — | 1% |
| Epoch Capabilities Index | — | 127.48 |

## Math

- Mercury 2: —
- Mistral Small 3.1: 13.7 (#295)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| OTIS Mock AIME 2024-2025 | — | 3.9% |
| Omni-MATH | — | 24.8% |
| LMArena Math | — | 1261 |

## Knowledge

- Mercury 2: 35.6 (#170)
- Mistral Small 3.1: 22.6 (#266)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Expert | 1358 | 1258 |
| GPQA Diamond | — | 41.9% |
| MMLU-Pro | — | 61% |
| Vectara Hallucination Rate | 12.3% | — |
| GPQA (HELM) | — | 39.2% |

## Multimodal

- Mercury 2: —
- Mistral Small 3.1: 32.6 (#93)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Vision | — | 1136 |

## Multilingual

- Mercury 2: 46.8 (#153)
- Mistral Small 3.1: 41.4 (#204)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Non-English | 1331 | 1255 |
| LMArena Chinese | 1416 | 1254 |
| LMArena Russian | 1303 | 1263 |
| LMArena French | — | 1270 |
| LMArena German | — | 1266 |
| LMArena Japanese | — | 1210 |
| LMArena Korean | — | 1206 |
| LMArena Spanish | — | 1283 |

## Instruction Following

- Mercury 2: 70.4 (#161)
- Mistral Small 3.1: 63.8 (#225)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Instruction Following | 1328 | 1264 |
| IFEval | — | 75% |

## Long Context

- Mercury 2: 40.4 (#149)
- Mistral Small 3.1: 39.5 (#172)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Longer Query | 1329 | 1300 |

## Writing & Preference

- Mercury 2: 54.0 (#151)
- Mistral Small 3.1: 37.2 (#254)

| Benchmark | Mercury 2 | Mistral Small 3.1 |
|---|---|---|
| LMArena Text | 1355 | 1278 |
| LMArena Creative Writing | 1289 | 1253 |
| LMArena Multi-Turn | 1358 | 1270 |
| EQ-Bench Creative Writing | — | 761 |
| WildBench | — | 78.8% |

## FAQ

### Is Mercury 2 better than Mistral Small 3.1?

Mercury 2 is the stronger model overall, scoring 38.8 to 31.4 on the Noometry Index.

### Which is cheaper, Mercury 2 or Mistral Small 3.1?

Mercury 2 is cheaper. It lists at $0.25 per million input tokens and $0.75 per million output tokens; Mistral Small 3.1 lists at $0.35 and $0.56.

### Is Mercury 2 or Mistral Small 3.1 better for coding?

Mistral Small 3.1 scores higher on coding benchmarks: 37.7 versus 33.2 in the Noometry coding category.

### Which has the bigger context window?

Both accept 128K tokens.

### How many benchmarks do Mercury 2 and Mistral Small 3.1 share?

11 benchmarks have published results for both models. Mercury 2 has 17 scored results on Noometry and Mistral Small 3.1 has 28.