# GPT-5.5 Pro vs Mistral Medium 3.1

> GPT-5.5 Pro is the stronger model overall, scoring 64.3 to 31.5 on the Noometry Index. Mistral Medium 3.1 costs 84× less per token, which makes it the better buy when GPT-5.5 Pro's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-5-5-pro-vs-mistral-medium-3-1
- Last updated: 2026-10-10
- Shared benchmarks: 0

## Summary

- The widest gap is in reasoning, where GPT-5.5 Pro leads 73.6 to 10.1.
- Mistral Medium 3.1 is cheaper at $0.40 / $2 per million input/output tokens, against $30 / $180 for GPT-5.5 Pro.
- GPT-5.5 Pro accepts more context: 1.05M tokens versus 131K.

## Snapshot

| | GPT-5.5 Pro | Mistral Medium 3.1 |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Noometry Index | 64.3 | 31.5 |
| Rank | 7 | 260 |
| Context | 1.05M | 131K |
| Input $/M | $30 | $0.40 |
| Output $/M | $180 | $2 |
| Weights | Proprietary | Proprietary |

## Reasoning

- GPT-5.5 Pro: 73.6 (#7)
- Mistral Medium 3.1: 10.1 (#336)

| Benchmark | GPT-5.5 Pro | Mistral Medium 3.1 |
|---|---|---|
| ARC-AGI-2 | 84.6% | — |
| SimpleBench | 76.9% | — |
| NYT Connections (extended) | — | 6.5% |
| ARC-AGI-1 | 96.5% | — |
| CritPt | 30.6% | — |
| Chess Puzzles | 64% | — |
| Thematic Generalization | — | 20.3% |
| DTBench | 96% | — |
| LMCA | 53.9% | — |
| Epoch Capabilities Index | 162.45 | — |

## Math

- GPT-5.5 Pro: 83.8 (#8)
- Mistral Medium 3.1: —

| Benchmark | GPT-5.5 Pro | Mistral Medium 3.1 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 87.7% | — |
| FrontierMath Tier 4 | 78% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| FrontierMath (Feb 2025 set) | 52.4% | — |
| FrontierMath Tier 4 (v1) | 39.6% | — |

## Knowledge

- GPT-5.5 Pro: 64.2 (#17)
- Mistral Medium 3.1: —

| Benchmark | GPT-5.5 Pro | Mistral Medium 3.1 |
|---|---|---|
| GPQA Diamond | 93.9% | — |

## Writing & Preference

- GPT-5.5 Pro: —
- Mistral Medium 3.1: 55.6 (#140)

| Benchmark | GPT-5.5 Pro | Mistral Medium 3.1 |
|---|---|---|
| EQ-Bench Creative Writing | — | 1476 |

## FAQ

### Is GPT-5.5 Pro better than Mistral Medium 3.1?

GPT-5.5 Pro is the stronger model overall, scoring 64.3 to 31.5 on the Noometry Index. Mistral Medium 3.1 costs 84× less per token, which makes it the better buy when GPT-5.5 Pro's lead doesn't matter for your workload.

### Which is cheaper, GPT-5.5 Pro or Mistral Medium 3.1?

Mistral Medium 3.1 is cheaper. It lists at $0.40 per million input tokens and $2 per million output tokens; GPT-5.5 Pro lists at $30 and $180.

### Which has the bigger context window?

GPT-5.5 Pro does, with 1.05M tokens against 131K.

### How many benchmarks do GPT-5.5 Pro and Mistral Medium 3.1 share?

0 benchmarks have published results for both models. GPT-5.5 Pro has 14 scored results on Noometry and Mistral Medium 3.1 has 3.