A low-cost Grok option for tool-heavy agents with a 1M-token context; UK availability isn't stated and older Grok 4 slugs now land here.
Kenning's take
What it does
Grok 4.3 is a SpaceXAI (formerly xAI) model for fast, reliable tool calling and instruction following, with a 1 million token context window. It takes text and images and has adjustable reasoning, from none up to xhigh. It is the API model that older Grok 4 and Grok 4.1 slugs were redirected to when they retired on 15 May 2026.
- 1M-token context window
- Reasoning effort from none to xhigh
- Function calling and structured outputs
- Text and image input
- Batch API support
Who it suits. Developers who want a cheap Grok model for agents and tool-heavy apps.
Key facts
- Category
- AI models
- Part of
- Grok
- Made by
- SpaceXAI (formerly xAI)
- Based in
- United States
- Released
- 30 April 2026
- How to get it
- xAI API (model grok-4.3); also listed on Vercel AI Gateway
- Works on
- API
- API price
- $1.25 per million input tokens, $2.50 per million output
FAQ
When was Grok 4.3 released?
Vercel's AI Gateway lists it from 30 April 2026.
How much does Grok 4.3 cost?
$1.25 per million input tokens and $2.50 per million output tokens.
How big is Grok 4.3's context window?
1 million tokens.
Facts from the maker's own pages and the sources listed. Checked 2026-10-11.
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