Grok 4.20 BetavsGrok Code Fast 1
Grok 4.20 Beta | Grok Code Fast 1 | |
|---|---|---|
| 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 | $1.00 |
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 | $2.00 |
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 | $0.20 |
| Benchmarks | ||
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% | 70.8% |
| 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. | 56% | — |
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 | Feb 17 2026 | Aug 28 2025 |
| Access | Proprietary | Proprietary |
Other comparisons
Frequently asked questions
Grok 4.20 Beta leads Grok Code Fast 1 on 1 of the 1 benchmark they both report (SWE-Bench Verified). Grok Code Fast 1 is cheaper on both input and output: $1.00 vs $1.25 per million input tokens, and $2.00 vs $2.50 per million output tokens. Figures are base-tier rates. Grok Code Fast 1 shipped 173 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 SWE-Bench Verified, Grok 4.20 Beta leads at 76.7% vs Grok Code Fast 1 at 70.8%.
Grok 4.20 Beta was released by SpaceXAI on Feb 17 2026.
Grok Code Fast 1 was released by SpaceXAI on Aug 28 2025.
Grok 4.20 Beta leads on SWE-Bench Verified — Grok 4.20 Beta 76.7% vs Grok Code Fast 1 70.8%.
Grok Code Fast 1 is cheaper on both input and output: $1.00 vs $1.25 per million input tokens, and $2.00 vs $2.50 per million output tokens. Figures are base-tier rates. Rates are pay-as-you-go API prices verified on August 18, 2026.