Grok Code Fast 1 changelog

Every change to Grok Code Fast 1 that Modelpeers has recorded, newest first, each with the source it came from. The record starts May 15, 2026.

May 2026

Grok 4.1 Fast, 4, Code Fast 1

5 products from SpaceXSI

Retired

xAI retires older Grok models, requests redirect to Grok 4.3

On May 15, 2026 xAI retired grok-4-1-fast, grok-4-fast, grok-4-0709, grok-code-fast-1, grok-3 and grok-imagine-image-pro. Requests to these slugs redirect to grok-4.3 (or grok-build-0.1 for grok-code-fast-1) and are billed at grok-4.3 rates of $1.25 input and $2.50 output per 1M tokens.

After

grok-4.3 at $1.25 / $2.50 per 1M tokens

Who is affected:
Apps still calling the retired Grok slugs, which now get a different model at a different price.
Action needed:
Set the model explicitly to grok-4.3 with the reasoning effort you want, or grok-build-0.1 for coding.

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