GPT-5.1vsGrok Code Fast 1
GPT-5.1 | 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. | $10.00 | $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. | $0.125 | $0.20 |
Cheapest inputLowest input rate across third-party providers, excluding the lab itself. The cheapest endpoint may run a quantised build or a shorter context — see "Available from" on the model page. | $1.25Azure | — |
Cheapest outputLowest output rate across third-party providers, excluding the lab itself. May come from a different provider than the cheapest input. | $10.00Azure | — |
| 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. | 76.3% | 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. | 25% | — |
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 88.1% | — |
MMMUMultimodal — Tests the AI on understanding images and text together across many college subjects. Higher is better. | 76% | — |
| Overview | ||
| Company | OpenAI | SpaceXAI |
| Release date | Nov 12 2025 | Aug 28 2025 |
| Access | Proprietary | Proprietary |
Other comparisons
Frequently asked questions
GPT-5.1 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 $10.00 per million output tokens. Figures are base-tier rates. Grok Code Fast 1 shipped 76 days before GPT-5.1, 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, GPT-5.1 leads at 76.3% vs Grok Code Fast 1 at 70.8%.
GPT-5.1 was released by OpenAI on Nov 12 2025.
Grok Code Fast 1 was released by SpaceXAI on Aug 28 2025.
GPT-5.1 leads on SWE-Bench Verified — GPT-5.1 76.3% 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 $10.00 per million output tokens. Figures are base-tier rates. Rates are pay-as-you-go API prices verified on August 18, 2026.