Claude Sonnet 4.5 vs DeepSeek-V4-Pro
Anthropic Claude Sonnet 4.5 | DeepSeek DeepSeek-V4-Pro | |
|---|---|---|
| Overview | ||
| Company | Anthropic | DeepSeek |
| Release date | Sep 29 2025 | Apr 24 2026 |
| Access | Proprietary | Open Weight |
| 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%Best | 14% |
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% | — |
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% | 90.1%Best |
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 207 days before DeepSeek-V4-Pro | |
Which is better: Claude Sonnet 4.5 or DeepSeek-V4-Pro?
Claude Sonnet 4.5 and DeepSeek-V4-Pro are evenly matched across the 2 benchmarks they both report (BullshitBench v2, GPQA Diamond). Claude Sonnet 4.5 shipped 207 days before DeepSeek-V4-Pro, so benchmark comparisons should account for the intervening progress.
Claude Sonnet 4.5 is proprietary, while DeepSeek-V4-Pro is open weight.
On BullshitBench v2, Claude Sonnet 4.5 leads at 79% vs DeepSeek-V4-Pro at 14%. On GPQA Diamond, DeepSeek-V4-Pro leads at 90.1% vs Claude Sonnet 4.5 at 83.4%.
Frequently asked questions
Claude Sonnet 4.5 was released by Anthropic on Sep 29 2025.
DeepSeek-V4-Pro was released by DeepSeek on Apr 24 2026.
DeepSeek-V4-Pro leads on GPQA Diamond — Claude Sonnet 4.5 83.4% vs DeepSeek-V4-Pro 90.1%.
Claude Sonnet 4.5 is a proprietary model released by Anthropic. DeepSeek-V4-Pro is an open weight model released by DeepSeek.