Mistral Devstral Small 2 (24B) vs OpenAI GPT-5-Codex — side-by-side specs.
Mistral Devstral Small 2 (24B) | OpenAI GPT-5-Codex | |
|---|---|---|
| Overview | ||
| Company | Mistral | OpenAI |
| Release date | Dec 9 2025 | Sep 15 2025 |
| Model type | — | — |
| Open source | Yes | No |
| Specifications | ||
Parameters | — | — |
Context window | — | — |
| Benchmarks | ||
Science reasoning GPQA Diamond | — | — |
Software engineering SWE-Bench Verified | — | — |
Multimodal understanding MMMU | — | — |
| Timeline | ||
| Release gap | GPT-5-Codex shipped 85 days before Devstral Small 2 (24B) | |
Devstral Small 2 (24B) and GPT-5-Codex do not have directly comparable benchmark scores published on GPQA Diamond, SWE-Bench Verified, or MMMU. GPT-5-Codex shipped 85 days before Devstral Small 2 (24B), so benchmark comparisons should account for the intervening progress.
Devstral Small 2 (24B) is an open-source / open-weight model; GPT-5-Codex is proprietary.
Direct benchmark comparisons are unavailable — at least one of these models has not published scores on GPQA Diamond, SWE-Bench Verified, or MMMU.