Claude 3.5 SonnetvsGrok 4.1 Fast
Claude 3.5 Sonnet | Grok 4.1 Fast | |
|---|---|---|
| Benchmarks | ||
BullshitBench v2Nonsense detection — Given 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% | 19% |
| BenchmarksPublished by one model only | ||
SWE-Bench VerifiedCoding — Real 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% | — |
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 59.4% | — |
| Overview | ||
| Company | Anthropic | SpaceXAI |
| Release date | Jun 20 2024 | Nov 19 2025 |
| Access | Proprietary | Proprietary |
Frequently asked questions
Claude 3.5 Sonnet leads Grok 4.1 Fast on 1 of the 1 benchmark they both report (BullshitBench v2). Claude 3.5 Sonnet shipped 517 days before Grok 4.1 Fast, 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, Claude 3.5 Sonnet leads at 45% vs Grok 4.1 Fast at 19%.
Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.
Grok 4.1 Fast was released by SpaceXAI on Nov 19 2025.
Other comparisons
Claude 3.5 SonnetvsGPT-5.6-CyberGrok 4.1 FastvsGPT-5.6-CyberClaude 3.5 SonnetvsGemini 3.7 FlashGrok 4.1 FastvsGemini 3.7 FlashClaude 3.5 SonnetvsMuse GlimmerGrok 4.1 FastvsMuse GlimmerClaude 3.5 SonnetvsDeepSeek-V4-Pro-0813Grok 4.1 FastvsDeepSeek-V4-Pro-0813Claude 3.5 SonnetvsMistral Medium 3.5Grok 4.1 FastvsMistral Medium 3.5Claude 3.5 SonnetvsKimi K3Grok 4.1 FastvsKimi K3