Changes from previous version
Pairs Grok 4.1 quality targets with Grok 4 Fast-style serving economics and latency.
Release Summary
Faster, lower-latency Grok 4.1 variant for real-time assistants and high-throughput API workloads.
Timeline
November 19, 2025
Grok 4.1 Fast released
xAI adds Grok 4.1 Fast two days after the Grok 4.1 launch.