GPT-4o minivsGrok 4.1 Fast
GPT-4o mini | Grok 4.1 Fast | |
|---|---|---|
| Specifications | ||
Context windowHow much text the model can hold in mind at once — your question, any documents you attach, the conversation so far, and its own reply. Go past it and the earliest part falls out of view. | 128k | — |
| API pricingUSD per 1M tokens · lower wins | ||
Input priceWhat you pay for everything you send the model — your question, plus any documents or earlier conversation you include with it. | $0.15 | — |
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. | $0.60 | — |
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. | $0.075 | — |
| 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. | 2% | 19% |
| BenchmarksPublished by one model only | ||
GPQA DiamondScience — Graduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 40.2% | — |
| Overview | ||
| Company | OpenAI | SpaceXAI |
| Release date | Jul 18 2024 | Nov 19 2025 |
| Access | Proprietary | Proprietary |
Frequently asked questions
Grok 4.1 Fast leads GPT-4o mini on 1 of the 1 benchmark they both report (BullshitBench v2). Only GPT-4o mini has a verified first-party API price: $0.15 per million input tokens and $0.60 per million output tokens. No pay-as-you-go API rate is tracked for Grok 4.1 Fast. GPT-4o mini shipped 489 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.
On BullshitBench v2, Grok 4.1 Fast leads at 19% vs GPT-4o mini at 2%.
GPT-4o mini was released by OpenAI on Jul 18 2024.
Grok 4.1 Fast was released by SpaceXAI on Nov 19 2025.
Only GPT-4o mini has a verified first-party API price: $0.15 per million input tokens and $0.60 per million output tokens. No pay-as-you-go API rate is tracked for Grok 4.1 Fast. Rates are pay-as-you-go API prices verified on August 18, 2026.