# GPT-5.3 Codex vs Mixtral 8x7B

> GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 27.1 on the Noometry Index. Mixtral 8x7B costs 6.9× 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-mixtral-8x7b
- 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 Mixtral 8x7B 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 32.8.
- Mixtral 8x7B is cheaper at $0.70 / $0.70 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Codex.
- GPT-5.3 Codex accepts more context: 400K tokens versus 32K.
- Mixtral 8x7B has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| Provider | OpenAI | Mistral AI |
| Noometry Index | 45.8 | 27.1 |
| Rank | 69 | 334 |
| Context | 400K | 32K |
| Input $/M | $1.75 | $0.70 |
| Output $/M | $14 | $0.70 |
| Weights | Proprietary | Open |

## Coding

- GPT-5.3 Codex: 48.6 (#56)
- Mixtral 8x7B: 32.8 (#269)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| SWE-bench Verified | 74.8% | — |
| LMArena WebDev | 1409 | — |
| WeirdML | 79.3% | — |
| LMArena Coding | — | 1126 |
| ALE-Bench | 1,655 | — |
| HumanEval+ | — | 39.6% |
| MBPP+ | — | 49.7% |

## Agentic & Tool Use

- GPT-5.3 Codex: 48.0 (#9)
- Mixtral 8x7B: —

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| Terminal-Bench | 78.4% | — |
| METR Time Horizons | 74.5% | — |
| Vending-Bench 2 | 5,940 | — |

## Reasoning

- GPT-5.3 Codex: —
- Mixtral 8x7B: 18.2 (#285)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| Epoch Capabilities Index | 156.77 | 118.47 |
| LMArena Hard Prompts | — | 1115 |
| DTBench | — | 49.6% |
| Adversarial NLI | — | 55.2% |
| ForecastBench | — | 56.3 |
| HellaSwag | — | 86.7% |
| PIQA | — | 83.6% |
| WinoGrande | — | 77.2% |

## Math

- GPT-5.3 Codex: —
- Mixtral 8x7B: 18.8 (#289)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| Omni-MATH | — | 10.5% |
| LMArena Math | — | 1147 |
| MATH Level 5 | — | 10% |
| GSM8K | — | 74.4% |

## Knowledge

- GPT-5.3 Codex: —
- Mixtral 8x7B: 11.0 (#301)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| GPQA Diamond | — | 30.6% |
| MMLU-Pro | — | 33.5% |
| GPQA (HELM) | — | 29.6% |
| LMArena Expert | — | 1088 |
| ARC (AI2) Challenge | — | 87.3% |
| MMLU | — | 70.6% |
| OpenBookQA | — | 85.8% |
| TriviaQA | — | 82.2% |

## Multilingual

- GPT-5.3 Codex: —
- Mixtral 8x7B: 29.6 (#266)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| LMArena Non-English | — | 1077 |
| LMArena Chinese | — | 1055 |
| LMArena French | — | 1166 |
| LMArena German | — | 1114 |
| LMArena Japanese | — | 931 |
| LMArena Korean | — | 968 |
| LMArena Russian | — | 1090 |
| LMArena Spanish | — | 1111 |

## Instruction Following

- GPT-5.3 Codex: —
- Mixtral 8x7B: 51.0 (#297)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| IFEval | — | 57.5% |
| LMArena Instruction Following | — | 1109 |

## Long Context

- GPT-5.3 Codex: —
- Mixtral 8x7B: 33.4 (#260)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| LMArena Longer Query | — | 1103 |

## Writing & Preference

- GPT-5.3 Codex: —
- Mixtral 8x7B: 34.2 (#270)

| Benchmark | GPT-5.3 Codex | Mixtral 8x7B |
|---|---|---|
| LMArena Text | — | 1132 |
| LMArena Creative Writing | — | 1109 |
| WildBench | — | 67.3% |
| LMArena Multi-Turn | — | 1115 |

## FAQ

### Is GPT-5.3 Codex better than Mixtral 8x7B?

GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 27.1 on the Noometry Index. Mixtral 8x7B costs 6.9× 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 Mixtral 8x7B?

Mixtral 8x7B is cheaper. It lists at $0.70 per million input tokens and $0.70 per million output tokens; GPT-5.3 Codex lists at $1.75 and $14.

### Is GPT-5.3 Codex or Mixtral 8x7B better for coding?

GPT-5.3 Codex scores higher on coding benchmarks: 48.6 versus 32.8 in the Noometry coding category.

### Which has the bigger context window?

GPT-5.3 Codex does, with 400K tokens against 32K.

### How many benchmarks do GPT-5.3 Codex and Mixtral 8x7B share?

1 benchmark has published results for both models. GPT-5.3 Codex has 8 scored results on Noometry and Mixtral 8x7B has 38.