# Devstral Medium vs GPT-5.5 Pro

> GPT-5.5 Pro has enough public results to be ranked (#8); Devstral Medium does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/devstral-medium-vs-gpt-5-5-pro
- Last updated: 2026-10-11
- Shared benchmarks: 0

## Summary

- The widest gap is in reasoning, where GPT-5.5 Pro leads 73.3 to 21.1.
- Devstral Medium 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 262K.
- Devstral Medium has downloadable open weights; the other is API-only.

## Snapshot

| | Devstral Medium | GPT-5.5 Pro |
|---|---|---|
| Provider | Mistral AI | OpenAI |
| Noometry Index | 30.1 | 64.3 |
| Rank | — | 8 |
| Context | 262K | 1.05M |
| Input $/M | $0.40 | $30 |
| Output $/M | $2 | $180 |
| Weights | Open | Proprietary |

## Coding

- Devstral Medium: 24.3
- GPT-5.5 Pro: —

| Benchmark | Devstral Medium | GPT-5.5 Pro |
|---|---|---|
| LMArena WebDev | 1076 | — |

## Reasoning

- Devstral Medium: 21.1
- GPT-5.5 Pro: 73.3 (#10)

| Benchmark | Devstral Medium | GPT-5.5 Pro |
|---|---|---|
| ARC-AGI-2 | — | 84.6% |
| SimpleBench | — | 76.9% |
| Kagi LLM Benchmark | 37.7% | — |
| ARC-AGI-1 | — | 96.5% |
| CritPt | — | 30.6% |
| Chess Puzzles | — | 64% |
| DTBench | — | 96% |
| LMCA | — | 53.9% |
| Epoch Capabilities Index | — | 162.07 |

## Math

- Devstral Medium: —
- GPT-5.5 Pro: 84.0 (#10)

| Benchmark | Devstral Medium | GPT-5.5 Pro |
|---|---|---|
| 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

- Devstral Medium: —
- GPT-5.5 Pro: 64.1 (#19)

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

## FAQ

### Is Devstral Medium better than GPT-5.5 Pro?

GPT-5.5 Pro has enough public results to be ranked (#8); Devstral Medium does not yet, so treat this comparison as directional.

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

Devstral Medium 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 262K.

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

0 benchmarks have published results for both models. Devstral Medium has 2 scored results on Noometry and GPT-5.5 Pro has 14.