Claude Sonnet 4vsDeepSeek-V4-Flash-0731
Claude Sonnet 4 | DeepSeek-V4-Flash-0731 | |
|---|---|---|
| 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. | 30% | 38%Best |
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. | 72.7% | — |
Agentic terminal coding Terminal-Bench 2.1Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? Higher is better. | — | 82.7% |
Personal tool use Toolathlon-VerifiedTests how well the AI uses everyday personal tools and apps to get things done — a human-checked version of Toolathlon. Higher is better. | — | 70.3% |
Cybersecurity CyberGymTests the AI on cybersecurity challenges — finding and exploiting software weaknesses inside a safe sandbox. Higher is better. | — | 76.7% |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 75.4% | — |
Business workflows AutomationBenchTests whether the AI can run real multi-step business workflows — the kind of end-to-end office processes companies want to automate — from start to finish. Higher is better. | — | 25.1% |
| Overview | ||
| Company | Anthropic | DeepSeek |
| Release date | May 22 2025 | Jul 31 2026 |
| Access | Proprietary | Proprietary |
Which is better: Claude Sonnet 4 or DeepSeek-V4-Flash-0731?
DeepSeek-V4-Flash-0731 leads Claude Sonnet 4 on 1 of the 1 benchmark they both report (BullshitBench v2). Claude Sonnet 4 shipped 435 days before DeepSeek-V4-Flash-0731, 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.
On BullshitBench v2, DeepSeek-V4-Flash-0731 leads at 38% vs Claude Sonnet 4 at 30%.
Frequently asked questions
Claude Sonnet 4 was released by Anthropic on May 22 2025.
DeepSeek-V4-Flash-0731 was released by DeepSeek on Jul 31 2026.
Other comparisons
Claude Sonnet 4vsGPT-5.6 SolDeepSeek-V4-Flash-0731vsGPT-5.6 SolClaude Sonnet 4vsGemini 3.6 FlashDeepSeek-V4-Flash-0731vsGemini 3.6 FlashClaude Sonnet 4vsMuse Spark 1.1DeepSeek-V4-Flash-0731vsMuse Spark 1.1Claude Sonnet 4vsGrok 4.5DeepSeek-V4-Flash-0731vsGrok 4.5Claude Sonnet 4vsMistral Medium 3.5DeepSeek-V4-Flash-0731vsMistral Medium 3.5Claude Sonnet 4vsKimi K3DeepSeek-V4-Flash-0731vsKimi K3