# GPT-5.3 Codex vs Mistral Medium 3.1

> GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 31.9 on the Noometry Index. Mistral Medium 3.1 costs 6.0× less per token, which makes it the better buy when GPT-5.3 Codex's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-5-3-codex-vs-mistral-medium-3-1
- Last updated: 2026-10-11
- Shared benchmarks: 0

## Summary

- Mistral Medium 3.1 is cheaper at $0.40 / $2 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Codex.
- GPT-5.3 Codex accepts more context: 400K tokens versus 131K.

## Snapshot

| | GPT-5.3 Codex | Mistral Medium 3.1 |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Noometry Index | 45.8 | 31.9 |
| Rank | 69 | 266 |
| Context | 400K | 131K |
| Input $/M | $1.75 | $0.40 |
| Output $/M | $14 | $2 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.3 Codex: 48.6 (#56)
- Mistral Medium 3.1: —

| Benchmark | GPT-5.3 Codex | Mistral Medium 3.1 |
|---|---|---|
| SWE-bench Verified | 74.8% | — |
| LMArena WebDev | 1409 | — |
| WeirdML | 79.3% | — |
| ALE-Bench | 1,655 | — |

## Agentic & Tool Use

- GPT-5.3 Codex: 48.0 (#9)
- Mistral Medium 3.1: —

| Benchmark | GPT-5.3 Codex | Mistral Medium 3.1 |
|---|---|---|
| Terminal-Bench | 78.4% | — |
| METR Time Horizons | 74.5% | — |
| Vending-Bench 2 | 5,940 | — |

## Reasoning

- GPT-5.3 Codex: —
- Mistral Medium 3.1: 10.6 (#341)

| Benchmark | GPT-5.3 Codex | Mistral Medium 3.1 |
|---|---|---|
| NYT Connections (extended) | — | 6.5% |
| Thematic Generalization | — | 20.3% |
| Epoch Capabilities Index | 156.77 | — |

## Writing & Preference

- GPT-5.3 Codex: —
- Mistral Medium 3.1: 55.5 (#145)

| Benchmark | GPT-5.3 Codex | Mistral Medium 3.1 |
|---|---|---|
| EQ-Bench Creative Writing | — | 1476 |

## FAQ

### Is GPT-5.3 Codex better than Mistral Medium 3.1?

GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 31.9 on the Noometry Index. Mistral Medium 3.1 costs 6.0× less per token, which makes it the better buy when GPT-5.3 Codex's lead doesn't matter for your workload.

### Which is cheaper, GPT-5.3 Codex 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-5.3 Codex lists at $1.75 and $14.

### Which has the bigger context window?

GPT-5.3 Codex does, with 400K tokens against 131K.

### How many benchmarks do GPT-5.3 Codex and Mistral Medium 3.1 share?

0 benchmarks have published results for both models. GPT-5.3 Codex has 8 scored results on Noometry and Mistral Medium 3.1 has 3.