# GPT-5.3 Codex vs Mistral Large 3

> GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 39.1 on the Noometry Index. Mistral Large 3 costs 13× 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-large-3
- Last updated: 2026-10-11
- Shared benchmarks: 1

## Summary

- They share 1 benchmark with published results for both. GPT-5.3 Codex scores higher in 1 category and Mistral Large 3 in 0 categories; one gap is clear of the uncertainty.
- The widest gap is in coding, where GPT-5.3 Codex leads 48.6 to 34.4.
- Mistral Large 3 is cheaper at $0.25 / $0.75 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Codex.
- GPT-5.3 Codex accepts more context: 400K tokens versus 262K.
- Mistral Large 3 has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Noometry Index | 45.8 | 39.1 |
| Rank | 69 | 176 |
| Context | 400K | 262K |
| Input $/M | $1.75 | $0.25 |
| Output $/M | $14 | $0.75 |
| Weights | Proprietary | Open |

## Coding

- GPT-5.3 Codex: 48.6 (#56)
- Mistral Large 3: 34.4 (#237)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| LMArena WebDev | 1409 | 1230 |
| SWE-bench Verified | 74.8% | — |
| WeirdML | 79.3% | — |
| LMArena Coding | — | 1448 |
| ALE-Bench | 1,655 | — |

## Agentic & Tool Use

- GPT-5.3 Codex: 48.0 (#9)
- Mistral Large 3: —

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| Terminal-Bench | 78.4% | — |
| METR Time Horizons | 74.5% | — |
| Vending-Bench 2 | 5,940 | — |

## Reasoning

- GPT-5.3 Codex: —
- Mistral Large 3: 15.2 (#319)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| Kagi LLM Benchmark | — | 50.9% |
| NYT Connections (extended) | — | 7.5% |
| Thematic Generalization | — | 23% |
| LMArena Hard Prompts | — | 1429 |
| Epoch Capabilities Index | 156.77 | — |

## Math

- GPT-5.3 Codex: —
- Mistral Large 3: 38.7 (#129)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| LMArena Math | — | 1414 |

## Knowledge

- GPT-5.3 Codex: —
- Mistral Large 3: 36.0 (#177)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| Vectara Hallucination Rate | — | 14.5% |
| LMArena Expert | — | 1421 |

## Multimodal

- GPT-5.3 Codex: —
- Mistral Large 3: 38.2 (#66)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| LMArena Vision | — | 1221 |

## Multilingual

- GPT-5.3 Codex: —
- Mistral Large 3: 52.5 (#84)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| LMArena Non-English | — | 1413 |
| LMArena Chinese | — | 1447 |
| LMArena French | — | 1455 |
| LMArena German | — | 1437 |
| LMArena Japanese | — | 1394 |
| LMArena Korean | — | 1384 |
| LMArena Russian | — | 1411 |
| LMArena Spanish | — | 1440 |

## Instruction Following

- GPT-5.3 Codex: —
- Mistral Large 3: 74.0 (#108)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| LMArena Instruction Following | — | 1403 |

## Long Context

- GPT-5.3 Codex: —
- Mistral Large 3: 43.1 (#105)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| LMArena Longer Query | — | 1413 |

## Writing & Preference

- GPT-5.3 Codex: —
- Mistral Large 3: 60.0 (#101)

| Benchmark | GPT-5.3 Codex | Mistral Large 3 |
|---|---|---|
| LMArena Text | — | 1428 |
| LMArena Creative Writing | — | 1386 |
| EQ-Bench Creative Writing | — | 1412 |
| LMArena Multi-Turn | — | 1429 |

## FAQ

### Is GPT-5.3 Codex better than Mistral Large 3?

GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 39.1 on the Noometry Index. Mistral Large 3 costs 13× 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 Large 3?

Mistral Large 3 is cheaper. It lists at $0.25 per million input tokens and $0.75 per million output tokens; GPT-5.3 Codex lists at $1.75 and $14.

### Is GPT-5.3 Codex or Mistral Large 3 better for coding?

GPT-5.3 Codex scores higher on coding benchmarks: 48.6 versus 34.4 in the Noometry coding category.

### Which has the bigger context window?

GPT-5.3 Codex does, with 400K tokens against 262K.

### How many benchmarks do GPT-5.3 Codex and Mistral Large 3 share?

1 benchmark has published results for both models. GPT-5.3 Codex has 8 scored results on Noometry and Mistral Large 3 has 24.