Kimi Linear vs GPT-5-Codex
Moonshot AI Kimi Linear | OpenAI GPT-5-Codex | |
|---|---|---|
| Overview | ||
| Company | Moonshot AI | OpenAI |
| Release date | Oct 2025 | Sep 15 2025 |
| Access | Open Weight | Proprietary |
| Specifications | ||
Parameters | 48B | — |
| 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. | — | 39% |
| Timeline | ||
| Release gap | GPT-5-Codex shipped 16 days before Kimi Linear | |
Which is better: Kimi Linear or GPT-5-Codex?
Kimi Linear and GPT-5-Codex don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-5-Codex shipped 16 days before Kimi Linear, so benchmark comparisons should account for the intervening progress.
Kimi Linear is open weight, while GPT-5-Codex is proprietary.
Direct benchmark comparisons are unavailable — Kimi Linear and GPT-5-Codex don't publish scores on any of the same benchmarks.
Frequently asked questions
Kimi Linear was released by Moonshot AI on Oct 2025.
GPT-5-Codex was released by OpenAI on Sep 15 2025.
Kimi Linear is an open weight model released by Moonshot AI. GPT-5-Codex is a proprietary model released by OpenAI.
Other comparisons
Kimi Linear vs Claude Sonnet 5GPT-5-Codex vs Claude Sonnet 5Kimi Linear vs Gemini OmniGPT-5-Codex vs Gemini OmniKimi Linear vs Muse Spark 1.1GPT-5-Codex vs Muse Spark 1.1Kimi Linear vs Grok 4.5GPT-5-Codex vs Grok 4.5Kimi Linear vs DeepSeek-V4-ProGPT-5-Codex vs DeepSeek-V4-ProKimi Linear vs Mistral Medium 3.5GPT-5-Codex vs Mistral Medium 3.5