grok-4-fast-non-reasoning
Summary
grok-4-fast-non-reasoning is a proprietary language model from xAI, released on 23 Sept 2025. It accepts text and images and generates text, with a 2M-token context window and up to 30K output tokens per response.
Fast Grok model for responsive chat, reasoning, and tool-assisted work
Last verified 17 Oct 2026. Every figure on this page links to its source.
Specifications
| Developer | xAI |
|---|---|
| Release date | 23 Sept 2025 [models.dev] |
| Status | Generally available [models.dev] |
| Weights | Proprietary (API only) [models.dev] |
| Context window | 2M (2,000,000 tokens) [models.dev] |
| Max output | 30K tokens [models.dev] |
| Knowledge cutoff | Jun 2025 [models.dev] |
| Input | Text and images [models.dev] |
| Output | Text [models.dev] |
| Reasoning mode | No [models.dev] |
| Tool calling | Yes [models.dev] |
grok-4-fast-non-reasoning API pricing by provider
USD per million tokens. Sorted by input price.
We do not currently track a paid API listing for this model.
Frequently asked questions
What is the context window of grok-4-fast-non-reasoning?
grok-4-fast-non-reasoning has a context window of 2,000,000 tokens (2M) and can generate up to 30,000 tokens in a single response, according to models.dev.
Is grok-4-fast-non-reasoning open source?
No. grok-4-fast-non-reasoning is a proprietary model; xAI has not released its weights.
When was grok-4-fast-non-reasoning released?
xAI released grok-4-fast-non-reasoning on 23 Sept 2025, according to models.dev.
Change history
- Added to the directory