Grok 2.5vsGrok 4.1 Fast
Grok 2.5 | Grok 4.1 Fast | |
|---|---|---|
| BenchmarksPublished by one model only | ||
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. | — | 19% |
| Overview | ||
| Company | SpaceXAI | SpaceXAI |
| Release date | Aug 23 2025 | Nov 19 2025 |
| Access | Proprietary | Proprietary |
Other comparisons
Grok 2.5vsClaude Fable 5.1Grok 4.1 FastvsClaude Fable 5.1Grok 2.5vsGPT-6 AstraGrok 4.1 FastvsGPT-6 AstraGrok 2.5vsGemini 3.8 FlashGrok 4.1 FastvsGemini 3.8 FlashGrok 2.5vsMuse Spark 1.3Grok 4.1 FastvsMuse Spark 1.3Grok 2.5vsDeepSeek-V4.1-FlashGrok 4.1 FastvsDeepSeek-V4.1-FlashGrok 2.5vsMistral Medium 3.5Grok 4.1 FastvsMistral Medium 3.5
Frequently asked questions
Grok 2.5 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 2.5 shipped 88 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 2.5 and Grok 4.1 Fast don't publish scores on any of the same benchmarks.