# GPT-5.5 Pro vs Mistral Small 4

> GPT-5.5 Pro has enough public results to be ranked (#7); Mistral Small 4 does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/gpt-5-5-pro-vs-mistral-small-4
- Last updated: 2026-10-10
- Shared benchmarks: 0

## Summary

- The widest gap is in reasoning, where GPT-5.5 Pro leads 73.6 to 21.2.
- Mistral Small 4 is cheaper at $0.075 / $0.30 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.
- Mistral Small 4 has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.5 Pro | Mistral Small 4 |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Noometry Index | 64.3 | 30.2 |
| Rank | 7 | — |
| Context | 1.05M | 262K |
| Input $/M | $30 | $0.075 |
| Output $/M | $180 | $0.30 |
| Weights | Proprietary | Open |

## Reasoning

- GPT-5.5 Pro: 73.6 (#7)
- Mistral Small 4: 21.2

| Benchmark | GPT-5.5 Pro | Mistral Small 4 |
|---|---|---|
| ARC-AGI-2 | 84.6% | — |
| SimpleBench | 76.9% | — |
| Kagi LLM Benchmark | — | 40.5% |
| ARC-AGI-1 | 96.5% | — |
| CritPt | 30.6% | — |
| Chess Puzzles | 64% | — |
| DTBench | 96% | — |
| LMCA | 53.9% | — |
| Epoch Capabilities Index | 162.45 | — |

## Math

- GPT-5.5 Pro: 83.8 (#8)
- Mistral Small 4: —

| Benchmark | GPT-5.5 Pro | Mistral Small 4 |
|---|---|---|
| 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 Small 4: —

| Benchmark | GPT-5.5 Pro | Mistral Small 4 |
|---|---|---|
| GPQA Diamond | 93.9% | — |

## FAQ

### Is GPT-5.5 Pro better than Mistral Small 4?

GPT-5.5 Pro has enough public results to be ranked (#7); Mistral Small 4 does not yet, so treat this comparison as directional.

### Which is cheaper, GPT-5.5 Pro or Mistral Small 4?

Mistral Small 4 is cheaper. It lists at $0.075 per million input tokens and $0.30 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 GPT-5.5 Pro and Mistral Small 4 share?

0 benchmarks have published results for both models. GPT-5.5 Pro has 14 scored results on Noometry and Mistral Small 4 has 1.