Claude 3.5 Sonnet vs DeepSeek V3.1 Terminus
Anthropic Claude 3.5 Sonnet | DeepSeek DeepSeek V3.1 Terminus | |
|---|---|---|
| Overview | ||
| Company | Anthropic | DeepSeek |
| Release date | Jun 20 2024 | Sep 22 2025 |
| 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. | 45% | — |
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. | 33.4% | — |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 59.4% | — |
| Timeline | ||
| Release gap | Claude 3.5 Sonnet shipped 459 days before DeepSeek V3.1 Terminus | |
Which is better: Claude 3.5 Sonnet or DeepSeek V3.1 Terminus?
Claude 3.5 Sonnet and DeepSeek V3.1 Terminus don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude 3.5 Sonnet shipped 459 days before DeepSeek V3.1 Terminus, so benchmark comparisons should account for the intervening progress.
Claude 3.5 Sonnet is proprietary, while DeepSeek V3.1 Terminus is open weight.
Direct benchmark comparisons are unavailable — Claude 3.5 Sonnet and DeepSeek V3.1 Terminus don't publish scores on any of the same benchmarks.
Frequently asked questions
Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.
DeepSeek V3.1 Terminus was released by DeepSeek on Sep 22 2025.
Claude 3.5 Sonnet is a proprietary model released by Anthropic. DeepSeek V3.1 Terminus is an open weight model released by DeepSeek.