Claude Sonnet 4.5 vs Mistral Medium 3.5
Anthropic Claude Sonnet 4.5 | Mistral Mistral Medium 3.5 | |
|---|---|---|
| Overview | ||
| Company | Anthropic | Mistral |
| Release date | Sep 29 2025 | Apr 29 2026 |
| Access | Proprietary | Open Weight |
| Specifications | ||
Parameters | — | 128B |
Context window | — | 256k |
| 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. | 79% | — |
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. | 77.2% | 77.6%Best |
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. | 50% | — |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 83.4% | — |
Multimodal MMMUTests the AI on understanding images and text together across many college subjects. Higher is better. | 68% | — |
| Timeline | ||
| Release gap | Claude Sonnet 4.5 shipped 212 days before Mistral Medium 3.5 | |
Which is better: Claude Sonnet 4.5 or Mistral Medium 3.5?
Mistral Medium 3.5 leads Claude Sonnet 4.5 on 1 of the 1 benchmark they both report (SWE-Bench Verified). Claude Sonnet 4.5 shipped 212 days before Mistral Medium 3.5, so benchmark comparisons should account for the intervening progress.
Claude Sonnet 4.5 is proprietary, while Mistral Medium 3.5 is open weight.
On SWE-Bench Verified, Mistral Medium 3.5 leads at 77.6% vs Claude Sonnet 4.5 at 77.2%.
Frequently asked questions
Claude Sonnet 4.5 was released by Anthropic on Sep 29 2025.
Mistral Medium 3.5 was released by Mistral on Apr 29 2026.
Mistral Medium 3.5 leads on SWE-Bench Verified — Claude Sonnet 4.5 77.2% vs Mistral Medium 3.5 77.6%.
Claude Sonnet 4.5 is a proprietary model released by Anthropic. Mistral Medium 3.5 is an open weight model released by Mistral.
Other comparisons
Claude Sonnet 4.5 vs GPT-5.6 SolMistral Medium 3.5 vs GPT-5.6 SolClaude Sonnet 4.5 vs Gemini OmniMistral Medium 3.5 vs Gemini OmniClaude Sonnet 4.5 vs Muse Spark 1.1Mistral Medium 3.5 vs Muse Spark 1.1Claude Sonnet 4.5 vs Grok 4.5Mistral Medium 3.5 vs Grok 4.5Claude Sonnet 4.5 vs DeepSeek-V4-ProMistral Medium 3.5 vs DeepSeek-V4-ProClaude Sonnet 4.5 vs Kimi K2.7 CodeMistral Medium 3.5 vs Kimi K2.7 Code