# GPT-5-Codex vs o1-mini

> GPT-5-Codex is the stronger model overall, scoring 37.9 to 34.0 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-codex-vs-o1-mini
- Last updated: 2026-10-12
- Shared benchmarks: 1

## Summary

- They share 1 benchmark with published results for both. GPT-5-Codex scores higher in 3 categories and o1-mini in 0 categories; 3 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5-Codex leads 30.9 to 8.8.
- The biggest single-benchmark swing is WeirdML: 54.5% for GPT-5-Codex and 36.3% for o1-mini.

## Snapshot

| | GPT-5-Codex | o1-mini |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 37.9 | 34.0 |
| Rank | 192 | 235 |
| Context | 400K | — |
| Input $/M | $1.25 | — |
| Output $/M | $10 | — |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5-Codex: 42.4 (#103)
- o1-mini: 35.5 (#224)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| WeirdML | 54.5% | 36.3% |
| Aider Polyglot | — | 32.9% |
| LiveBench Coding | — | 48% |
| LMArena Coding | — | 1362 |
| HumanEval+ | — | 89% |
| MBPP+ | — | 78.8% |

## Agentic & Tool Use

- GPT-5-Codex: 31.0 (#72)
- o1-mini: 24.6 (#118)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| Terminal-Bench | 44.3% | — |
| Cybench | — | 10% |

## Reasoning

- GPT-5-Codex: 30.9 (#83)
- o1-mini: 8.8 (#346)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| ARC-AGI-2 | — | 0.8% |
| SimpleBench | — | 18.1% |
| Kagi LLM Benchmark | 70.3% | — |
| ARC-AGI-1 | — | 14% |
| LiveBench Reasoning | — | 72.3% |
| LMArena Hard Prompts | — | 1333 |
| LiveBench Data Analysis | — | 57.9% |
| Epoch Capabilities Index | — | 135.82 |
| LiveBench | — | 57.8% |

## Math

- GPT-5-Codex: —
- o1-mini: 35.4 (#186)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| OTIS Mock AIME 2024-2025 | — | 46.9% |
| LiveBench Math | — | 62% |
| LMArena Math | — | 1358 |
| MATH Level 5 | — | 89.2% |
| FrontierMath (Feb 2025 set) | — | 1.7% |

## Knowledge

- GPT-5-Codex: —
- o1-mini: 34.9 (#192)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| GPQA Diamond | — | 62.4% |
| Confabulations | — | 18.6% |
| LMArena Expert | — | 1316 |

## Multilingual

- GPT-5-Codex: —
- o1-mini: 43.6 (#182)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| LMArena Non-English | — | 1289 |
| LMArena Chinese | — | 1314 |
| LMArena French | — | 1293 |
| LMArena German | — | 1278 |
| LMArena Japanese | — | 1245 |
| LMArena Korean | — | 1223 |
| LMArena Russian | — | 1283 |
| LMArena Spanish | — | 1303 |

## Instruction Following

- GPT-5-Codex: —
- o1-mini: 66.7 (#206)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| LiveBench Instruction Following | — | 65.4% |
| LMArena Instruction Following | — | 1304 |

## Long Context

- GPT-5-Codex: —
- o1-mini: 40.1 (#161)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| LMArena Longer Query | — | 1320 |

## Writing & Preference

- GPT-5-Codex: —
- o1-mini: 48.4 (#202)

| Benchmark | GPT-5-Codex | o1-mini |
|---|---|---|
| LMArena Text | — | 1317 |
| LMArena Creative Writing | — | 1244 |
| Short-Story Creative Writing | — | 64.9% |
| LMArena Multi-Turn | — | 1314 |
| LiveBench Language | — | 40.9% |

## FAQ

### Is GPT-5-Codex better than o1-mini?

GPT-5-Codex is the stronger model overall, scoring 37.9 to 34.0 on the Noometry Index.

### Is GPT-5-Codex or o1-mini better for coding?

GPT-5-Codex scores higher on coding benchmarks: 42.4 versus 35.5 in the Noometry coding category.

### How many benchmarks do GPT-5-Codex and o1-mini share?

1 benchmark has published results for both models. GPT-5-Codex has 3 scored results on Noometry and o1-mini has 39.