Claude Haiku 4.5 vs GPT-5-Codex-Mini
Anthropic Claude Haiku 4.5 | OpenAI GPT-5-Codex-Mini | |
|---|---|---|
| Overview | ||
| Company | Anthropic | OpenAI |
| Release date | Oct 15 2025 | Nov 8 2025 |
| Access | Proprietary | Proprietary |
| 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. | 77% | — |
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | 73.3% | — |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 73% | — |
| Timeline | ||
| Release gap | Claude Haiku 4.5 shipped 24 days before GPT-5-Codex-Mini | |
Which is better: Claude Haiku 4.5 or GPT-5-Codex-Mini?
Claude Haiku 4.5 and GPT-5-Codex-Mini don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude Haiku 4.5 shipped 24 days before GPT-5-Codex-Mini, so benchmark comparisons should account for the intervening progress.
Published specifications for these two models are limited — see each model page for the latest details.
Direct benchmark comparisons are unavailable — Claude Haiku 4.5 and GPT-5-Codex-Mini don't publish scores on any of the same benchmarks.
Frequently asked questions
Claude Haiku 4.5 was released by Anthropic on Oct 15 2025.
GPT-5-Codex-Mini was released by OpenAI on Nov 8 2025.
Other comparisons
Claude Haiku 4.5 vs Gemini OmniGPT-5-Codex-Mini vs Gemini OmniClaude Haiku 4.5 vs Muse Spark 1.1GPT-5-Codex-Mini vs Muse Spark 1.1Claude Haiku 4.5 vs Grok 4.5GPT-5-Codex-Mini vs Grok 4.5Claude Haiku 4.5 vs DeepSeek-V4-ProGPT-5-Codex-Mini vs DeepSeek-V4-ProClaude Haiku 4.5 vs Mistral Medium 3.5GPT-5-Codex-Mini vs Mistral Medium 3.5Claude Haiku 4.5 vs Kimi K2.7 CodeGPT-5-Codex-Mini vs Kimi K2.7 Code