# GPT-5.1-Codex vs Molmo 2 8b

> GPT-5.1-Codex and Molmo 2 8b score almost the same on the Noometry Index (38.6 vs 39.1), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/gpt-5-1-codex-vs-molmo-2-8b
- Last updated: 2026-10-11
- Shared benchmarks: 0

## Summary

- Molmo 2 8b has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| Provider | OpenAI | Allen Institute for AI (Ai2) |
| Noometry Index | 38.6 | 39.1 |
| Rank | 186 | 174 |
| Context | 400K | — |
| Input $/M | $1.25 | — |
| Output $/M | $10 | — |
| Weights | Proprietary | Open |

## Coding

- GPT-5.1-Codex: 41.9 (#116)
- Molmo 2 8b: —

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| SWE-bench Verified (bash only) | 66% | — |
| LMArena WebDev | 1337 | — |
| ALE-Bench | 1,245 | — |

## Agentic & Tool Use

- GPT-5.1-Codex: 38.0 (#33)
- Molmo 2 8b: —

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| Terminal-Bench | 60.4% | — |
| METR Time Horizons | 70.8% | — |

## Reasoning

- GPT-5.1-Codex: —
- Molmo 2 8b: 25.6 (#146)

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| LMArena Hard Prompts | — | 1287 |

## Math

- GPT-5.1-Codex: 30.3 (#235)
- Molmo 2 8b: —

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| ProofBench | 9% | — |

## Multimodal

- GPT-5.1-Codex: —
- Molmo 2 8b: 30.2 (#112)

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| LMArena Vision | — | 1081 |

## Multilingual

- GPT-5.1-Codex: —
- Molmo 2 8b: 42.7 (#190)

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| LMArena Non-English | — | 1276 |

## Instruction Following

- GPT-5.1-Codex: —
- Molmo 2 8b: 67.0 (#201)

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| LMArena Instruction Following | — | 1270 |

## Writing & Preference

- GPT-5.1-Codex: —
- Molmo 2 8b: 49.4 (#191)

| Benchmark | GPT-5.1-Codex | Molmo 2 8b |
|---|---|---|
| LMArena Text | — | 1288 |

## FAQ

### Is GPT-5.1-Codex better than Molmo 2 8b?

GPT-5.1-Codex and Molmo 2 8b score almost the same on the Noometry Index (38.6 vs 39.1), so choose on price, context window or the category you care about most.

### How many benchmarks do GPT-5.1-Codex and Molmo 2 8b share?

0 benchmarks have published results for both models. GPT-5.1-Codex has 6 scored results on Noometry and Molmo 2 8b has 5.