Grok 4.1 Fast Lands on All Platforms: 50% Price Cut, 2M Context Window, Four New API Features
xAI's Grok 4.1 is now live across every major surface — grok.com, X, iOS, and Android — with the faster Grok 4.1 Fast variant simultaneously rolling out on the xAI Enterprise API. The release is headlined by an aggressive pricing reset: input tokens drop to $0.20 per million (roughly one-fifteenth of Grok 4's cost), and output falls to $0.50 per million, with agentic tool-call pricing slashed by up to 50%. For developers running document-heavy pipelines or high-frequency agent loops, the math has changed substantially.
Under the hood, four new capabilities ship with the launch: Collections Search, Remote MCP Tools, Live Search moving to general availability, and a Voice Agent API now open to all API users. The model also expands its context window from 256K to 2M tokens — an eightfold increase — while cutting hallucination rates by 65%, dropping from 12.09% to 4.22% on internal benchmarks. Grok 4.1 Thinking mode has already claimed the top position on LMArena's Text Arena leaderboard, putting it ahead of rivals at a fraction of the price.
The combination of frontier-tier context length, lower error rates, and sub-cent-per-thousand-token pricing positions Grok 4.1 Fast as one of the most cost-effective long-context options available at the frontier right now. Teams evaluating xAI's API for real-time search integrations, MCP-powered workflows, or long-document analysis have a genuinely new entry point to consider.