Grok 4.1 FastvsGrok 4.20 Beta
Grok 4.1 Fast | Grok 4.20 Beta | |
|---|---|---|
| API pricingUSD per 1M tokens · lower wins · base tier | ||
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it. | — | $1.25 |
Output priceWhat you pay for the text the model writes back. It is normally the dearer half: producing an answer costs more than reading one. | — | $2.50 |
Cached input priceA reduced rate for text you send over and over. If every request starts with the same instructions or the same document, the provider keeps a copy ready and charges less to read it again. | — | $0.20 |
| 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. | 19% | 56% |
| 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. | — | 76.7% |
ARC-AGI-2Abstract reasoning — Puzzle-style tests of abstract reasoning and pattern-finding — the kind of thing people find easy but AIs often struggle with. Higher is better. | — | 53.3% |
| Overview | ||
| Company | SpaceXAI | SpaceXAI |
| Release date | Nov 19 2025 | Feb 17 2026 |
| Access | Proprietary | Proprietary |
Other comparisons
Grok 4.1 FastvsClaude Fable 5.1Grok 4.20 BetavsClaude Fable 5.1Grok 4.1 FastvsGPT-6 AstraGrok 4.20 BetavsGPT-6 AstraGrok 4.1 FastvsGemini 3.8 FlashGrok 4.20 BetavsGemini 3.8 FlashGrok 4.1 FastvsMuse Spark 1.3Grok 4.20 BetavsMuse Spark 1.3Grok 4.1 FastvsDeepSeek-V4.1-FlashGrok 4.20 BetavsDeepSeek-V4.1-FlashGrok 4.1 FastvsMistral Medium 3.5Grok 4.20 BetavsMistral Medium 3.5
Frequently asked questions
Grok 4.20 Beta leads Grok 4.1 Fast on 1 of the 1 benchmark they both report (BullshitBench v2). Only Grok 4.20 Beta has a verified first-party API price: $1.25 per million input tokens and $2.50 per million output tokens. No pay-as-you-go API rate is tracked for Grok 4.1 Fast. Grok 4.1 Fast shipped 90 days before Grok 4.20 Beta, 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, Grok 4.20 Beta leads at 56% vs Grok 4.1 Fast at 19%.