Grok 4 Fast vs Grok 4.1 Fast
SpaceXAI Grok 4 Fast | SpaceXAI Grok 4.1 Fast | |
|---|---|---|
| Overview | ||
| Company | SpaceXAI | SpaceXAI |
| Release date | Sep 2025 | Nov 19 2025 |
| Access | Proprietary | Proprietary |
| 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. | — | 19% |
| Timeline | ||
| Release gap | Grok 4 Fast shipped 79 days before Grok 4.1 Fast | |
Which is better: Grok 4 Fast or Grok 4.1 Fast?
Grok 4 Fast and Grok 4.1 Fast don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Grok 4 Fast shipped 79 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.
Direct benchmark comparisons are unavailable — Grok 4 Fast and Grok 4.1 Fast don't publish scores on any of the same benchmarks.
Frequently asked questions
Grok 4 Fast was released by SpaceXAI on Sep 2025.
Grok 4.1 Fast was released by SpaceXAI on Nov 19 2025.
Other comparisons
Grok 4 Fast vs Claude Sonnet 5Grok 4.1 Fast vs Claude Sonnet 5Grok 4 Fast vs GPT-5.6 SolGrok 4.1 Fast vs GPT-5.6 SolGrok 4 Fast vs Gemini OmniGrok 4.1 Fast vs Gemini OmniGrok 4 Fast vs Muse Spark 1.1Grok 4.1 Fast vs Muse Spark 1.1Grok 4 Fast vs DeepSeek-V4-ProGrok 4.1 Fast vs DeepSeek-V4-ProGrok 4 Fast vs Mistral Medium 3.5Grok 4.1 Fast vs Mistral Medium 3.5