# xAI Grok 4 Fast Non-Reasoning — deprecation status

> Yes — Grok 4 Fast Non-Reasoning is retired. xAI shut it down on May 15, 2026; API requests to it now fail. The recommended replacement is Grok 4.3.

The non-thinking half of Grok 4 Fast, and the cheapest id xAI has ever served. It was the natural home for classification and extraction jobs at volume, which makes it the one in this wave most likely to be sitting in a batch pipeline nobody has looked at since it was written.

## Facts

| Field | Value |
| --- | --- |
| Provider | xAI |
| Model id | `grok-4-fast-non-reasoning` |
| Status | Retired |
| Shutdown | May 15, 2026 (80 days ago) |
| Last verified | August 3, 2026 |

## Replacement

- **Grok 4.3** (`grok-4.3`) · recommended — https://modeldeprecations.dev/xai/grok-4.3
  - Maps to grok-4.3 with reasoning effort "none". This is the largest price jump in the wave: a high-volume extraction job that cost pennies on this id is now billed at flagship rates.
  - Parameters it accepts: https://modelparams.dev/models/xai/grok-4.3

```diff
- "model": "grok-4-fast-non-reasoning"
+ "model": "grok-4.3"
```

## FAQ

### When did xAI Grok 4 Fast Non-Reasoning shut down?

xAI Grok 4 Fast Non-Reasoning shut down on May 15, 2026. API requests to it fail from that date onward.

### What replaces xAI Grok 4 Fast Non-Reasoning?

xAI recommends Grok 4.3 (`grok-4.3`) as the replacement for xAI Grok 4 Fast Non-Reasoning. Maps to grok-4.3 with reasoning effort "none". This is the largest price jump in the wave: a high-volume extraction job that cost pennies on this id is now billed at flagship rates.

### Is xAI Grok 4 Fast Non-Reasoning still available?

No. xAI Grok 4 Fast Non-Reasoning is retired and no longer served — it was shut down on May 15, 2026. Calls to it return an error.

### How do I migrate from xAI Grok 4 Fast Non-Reasoning to grok-4.3?

Swap the model id in your API call: replace "grok-4-fast-non-reasoning" with "grok-4.3". Maps to grok-4.3 with reasoning effort "none". This is the largest price jump in the wave: a high-volume extraction job that cost pennies on this id is now billed at flagship rates.

## Sources

- [Grok Model Retirement on May 15, 2026](https://docs.x.ai/developers/migration/may-15-retirement) — accessed 2026-08-03

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Canonical page: https://modeldeprecations.dev/xai/grok-4-fast-non-reasoning
JSON: https://modeldeprecations.dev/api/v1/models/xai/grok-4-fast-non-reasoning.json