AI Model

Grok 4 Heavy

Released on July 9, 2025

Changes from previous version

Uses additional test-time compute versus standard Grok 4 for tougher multi-step problems while sharing the same July 2025 launch window.

Release Summary

Higher-compute Grok 4 variant aimed at the hardest reasoning, math, and agentic workloads in the Grok 4 generation.

Timeline

July 9, 2025

Grok 4 Heavy released

xAI ships Grok 4 Heavy alongside the standard Grok 4 model.