# GPT-5.1-Codex vs Olmo 3.1 32b Instruct

> GPT-5.1-Codex and Olmo 3.1 32b Instruct score almost the same on the Noometry Index (38.2 vs 38.8), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/gpt-5-1-codex-vs-olmo-3-1-32b-instruct
- Last updated: 2026-10-10
- Shared benchmarks: 0

## Summary

- The widest gap is in math, where Olmo 3.1 32b Instruct leads 33.6 to 29.3.
- Olmo 3.1 32b Instruct has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| Provider | OpenAI | Allen Institute for AI (Ai2) |
| Noometry Index | 38.2 | 38.8 |
| Rank | 178 | 168 |
| Context | 400K | — |
| Input $/M | $1.25 | — |
| Output $/M | $10 | — |
| Weights | Proprietary | Open |

## Coding

- GPT-5.1-Codex: 41.7 (#107)
- Olmo 3.1 32b Instruct: 38.9 (#154)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| SWE-bench Verified (bash only) | 66% | — |
| LMArena WebDev | 1337 | — |
| LMArena Coding | — | 1346 |
| ALE-Bench | 1,245 | — |

## Agentic & Tool Use

- GPT-5.1-Codex: 37.8 (#32)
- Olmo 3.1 32b Instruct: —

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| Terminal-Bench | 60.4% | — |
| METR Time Horizons | 70.8% | — |

## Reasoning

- GPT-5.1-Codex: —
- Olmo 3.1 32b Instruct: 25.4 (#131)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| LMArena Hard Prompts | — | 1322 |

## Math

- GPT-5.1-Codex: 29.3 (#218)
- Olmo 3.1 32b Instruct: 33.6 (#169)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| ProofBench | 9% | — |
| LMArena Math | — | 1305 |

## Knowledge

- GPT-5.1-Codex: —
- Olmo 3.1 32b Instruct: 35.4 (#175)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| LMArena Expert | — | 1307 |

## Multilingual

- GPT-5.1-Codex: —
- Olmo 3.1 32b Instruct: 42.8 (#185)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| LMArena Non-English | — | 1275 |
| LMArena Chinese | — | 1304 |
| LMArena French | — | 1328 |
| LMArena German | — | 1283 |
| LMArena Korean | — | 1206 |
| LMArena Russian | — | 1268 |
| LMArena Spanish | — | 1337 |

## Instruction Following

- GPT-5.1-Codex: —
- Olmo 3.1 32b Instruct: 68.8 (#182)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| LMArena Instruction Following | — | 1298 |

## Long Context

- GPT-5.1-Codex: —
- Olmo 3.1 32b Instruct: 39.9 (#161)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| LMArena Longer Query | — | 1312 |

## Writing & Preference

- GPT-5.1-Codex: —
- Olmo 3.1 32b Instruct: 50.4 (#179)

| Benchmark | GPT-5.1-Codex | Olmo 3.1 32b Instruct |
|---|---|---|
| LMArena Text | — | 1311 |
| LMArena Creative Writing | — | 1264 |
| LMArena Multi-Turn | — | 1309 |

## FAQ

### Is GPT-5.1-Codex better than Olmo 3.1 32b Instruct?

GPT-5.1-Codex and Olmo 3.1 32b Instruct score almost the same on the Noometry Index (38.2 vs 38.8), so choose on price, context window or the category you care about most.

### Is GPT-5.1-Codex or Olmo 3.1 32b Instruct better for coding?

GPT-5.1-Codex scores higher on coding benchmarks: 41.7 versus 38.9 in the Noometry coding category.

### How many benchmarks do GPT-5.1-Codex and Olmo 3.1 32b Instruct share?

0 benchmarks have published results for both models. GPT-5.1-Codex has 6 scored results on Noometry and Olmo 3.1 32b Instruct has 16.