xAI's fast agentic tool-calling model with a 2M context window; non-reasoning variant for low-latency responses
Grok 4.1 Fast by xai is offered by 3 providers on this page. Public prices are shown for 2 of them. Its reference price is $0.20 per 1M input tokens and $0.50 per 1M output tokens.
Artificial Analysis rates it 20.4 on the Intelligence Index. Against its lowest blended price of $0.275 per 1M, that is roughly 74 index points per dollar, which is the value ratio the leaderboards rank on.
The context window is 128,000 tokens at the reference host, but hosts report different limits, from 128,000 to 2,000,000, so the usable window depends on the provider you pick. It supports tool use and structured output. Accepted input modalities are Text and Image. Providers report the capability flags inconsistently, so verify a specific feature against the host you plan to use.
Quality is independently evaluated by Artificial Analysis. Speed/latency are model-level medians.
Sorted by blended price (input×0.75 + output×0.25) asc. The official channel always shows regardless of rank. Whether a gateway's low price is actually usable can't be verified.
Individual evaluations run by Artificial Analysis, on the same reasoning tier as the intelligence score above. Each benchmark has its own task set and harness, so rows are not comparable with one another. The Intelligence Index above draws on a different, newer set of evaluations.