Devstral Small vs GPT-5.3-Codex
Mistral Devstral Small | OpenAI GPT-5.3-Codex | |
|---|---|---|
| Overview | ||
| Company | Mistral | OpenAI |
| Release date | May 21 2025 | Feb 5 2026 |
| Access | Open Weight | Proprietary |
| Specifications | ||
Parameters | 24B | — |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | — | 24% |
Next.js coding Next.js EvalsVercel's open eval of how well AI coding agents build and migrate real Next.js apps — measured as the share of tasks the agent completes successfully. Higher is better. | — | 83% |
| Timeline | ||
| Release gap | Devstral Small shipped 260 days before GPT-5.3-Codex | |
Which is better: Devstral Small or GPT-5.3-Codex?
Devstral Small and GPT-5.3-Codex don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Devstral Small shipped 260 days before GPT-5.3-Codex, so benchmark comparisons should account for the intervening progress.
Devstral Small is open weight, while GPT-5.3-Codex is proprietary.
Direct benchmark comparisons are unavailable — Devstral Small and GPT-5.3-Codex don't publish scores on any of the same benchmarks.
Frequently asked questions
Devstral Small was released by Mistral on May 21 2025.
GPT-5.3-Codex was released by OpenAI on Feb 5 2026.
Devstral Small is an open weight model released by Mistral. GPT-5.3-Codex is a proprietary model released by OpenAI.
Other comparisons
Devstral Small vs Claude Sonnet 5GPT-5.3-Codex vs Claude Sonnet 5Devstral Small vs Gemini OmniGPT-5.3-Codex vs Gemini OmniDevstral Small vs Muse Spark 1.1GPT-5.3-Codex vs Muse Spark 1.1Devstral Small vs Grok 4.5GPT-5.3-Codex vs Grok 4.5Devstral Small vs DeepSeek-V4-ProGPT-5.3-Codex vs DeepSeek-V4-ProDevstral Small vs Kimi K2.7 CodeGPT-5.3-Codex vs Kimi K2.7 Code