Grok model releases

xAI's frontier update to Grok 4.5, released 2026-08-12. Built on the same reported 1.5-trillion-parameter V9 foundation as Grok 4.5, with gains coming from upgraded supervised fine-tuning and reinforcement learning rather than a new base. Supports a 500K-token context and configurable reasoning effort (low, medium, high default, xhigh). List pricing is $2 / $6 per 1M input/output tokens below 200K prompt tokens ($0.50 cached input), rising to $4 / $12 above 200K.

Rumored next major Grok model. Elon Musk said after GPT-5's launch that Grok 5 would arrive before the end of 2025, but no broad public Grok 5 release is logged in this catalog yet.

xAI's fourth-generation Grok line, preceding the later 4.x API updates already tracked in the catalog.

xAI's third-generation model family, introduced with stronger reasoning, search, and coding modes.

Second-generation Grok release with Grok-2 and Grok-2 mini for chat, coding, reasoning, and image-enabled product experiences.

Grok update with stronger reasoning and a 128K context window.

xAI's first Grok model, later released as open weights with a 314B-parameter MoE checkpoint.