New Delhi: Elon Musk-owned xAI has also launched Grok 4 Fast, a new AI which is based on a more affordable variant of its popular Grok 4 system. The model is designed to place both the enterprise and consumer applications together; it combines both the reasoning and non-reasoning power into a single framework. According to the company, this integration cuts the latency and costs and still maintains high performance across benchmarks.
Grok 4 Fast, as xAI claims, uses an average of 40% of the number of thinking tokens as Grok 4 and provides almost the same accuracy. The assertion was substantiated by independent testing by Artificial Analysis, which proved that the model uses up to 98% less spending to bring similar results. Initial tests showed its usefulness, with Grok 4 Fast achieving 85.7% on the GPQA Diamond test, 92% on AIME 2025 and 93.3% on HMMT 2025.
Efficiency and performance gains
SimpleQA and X Bench Deepsearch were also highly improved with a 95 percent pass rate on SimpleQA and a 74 percent pass rate on X Bench Deepsearch. It supports a 2 million token context window, which makes it more efficient in handling large and complex inputs. Reinforcement learning has optimised the system to provide the highest flexibility and speed at a low cost to businesses as well as individuals using the system.
Availability and pricing
Grok 4 Fast is already on grok.com, in the iOS and Android apps of xAI. The model is also deployed on third-party platforms like OpenRouter, Vercel AI Gateway, and the xAI API. Users have the option to use it free for a limited period on OpenRouter and Vercel. It has two variants, grok-4-fast-reasoning and grok-4-fast-non-reasoning, and both of them advocate the 2M token limit. Prices will begin at 0.20 per million input tokens, and scaling will be provided based on usage.