Description
Grok 4 Fast is xAI's latest multimodal model with SOTA cost-efficiency and a 2M token context window. It comes in two flavors: non-reasoning and reasoning. Read more about the model on xAI's [news post](http://x.ai/news/grok-4-fast). Reasoning can be enabled using the `reasoning` `enabled` parameter in the API. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#controlling-reasoning-tokens)
API Usage Examples
OpenAI Compatible Endpoint
Use this endpoint with any OpenAI-compatible library. Model: xAI: Grok 4 Fast (x-ai/grok-4-fast)
curl https://api.ridvay.com/v1/chat/completions -H "Content-Type: application/json" -H "Authorization: Bearer YOUR_API_KEY" -d '{
"model": "x-ai/grok-4-fast",
"messages": [
{
"role": "user",
"content": "Explain the capabilities of the xAI: Grok 4 Fast model"
}
],
"temperature": 0.7,
"max_tokens": 1024
}'Supported Modalities
- Text
- Images
API Pricing
- Input: 0.2$ / 1M tokens
- Output: 0.5$ / 1M tokens
Token Limits
- Max Output: 30,000 tokens
- Max Context: 2,000,000 tokens
Subscription Tiers
- free
- pro
- ultimate