xAI: Grok 3 Beta · fastrouter

Grok 3 Beta is xAI's flagship model featuring specialized domain expertise in finance, healthcare, law, and scientific fields. This enterprise-focused solution delivers exceptional performance in data extraction, code generation, and text summarization tasks. Released in 2025, the model particularly excels in structured tasks and achieves superior results on challenging benchmarks like GPQA, LCB, and MMLU-Pro, consistently outperforming the smaller Grok 3 Mini even when the latter operates at high thinking levels. Grok 3's sophisticated knowledge architecture makes it particularly valuable for professional and technical applications requiring deep contextual understanding in regulated industries. The model offers dual deployment options: a standard endpoint optimized for quality and a fast endpoint prioritizing throughput, allowing users to select the appropriate performance profile based on their specific application requirements.

Base model All models on this base All models of the provider to the provider

Input, $/1M $5.00

Output, $/1M $25.00

Cache read $1.25

Cache write —

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Last checked 04.11.2026 12:00:14 UTC

Source provider's page

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API

OpenAI-compatible API: the official OpenAI SDKs work with this base URL. Replace YOUR_API_KEY with your key from the provider.

API base URL	`https://go.fastrouter.ai/api/v1`
Endpoint	`https://go.fastrouter.ai/api/v1/chat/completions`
Model id	`x-ai/grok-3-beta`

curl

curl https://go.fastrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "x-ai/grok-3-beta", "messages": [{"role": "user", "content": "Hello!"}], "max_tokens": 256}'

Python

import requests

r = requests.post(
    "https://go.fastrouter.ai/api/v1/chat/completions",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
      "model": "x-ai/grok-3-beta",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ],
      "max_tokens": 256
    },
)
print(r.json())

JavaScript

const r = await fetch("https://go.fastrouter.ai/api/v1/chat/completions", {
  method: "POST",
  headers: {Authorization: "Bearer YOUR_API_KEY", "Content-Type": "application/json"},
  body: JSON.stringify({
    "model": "x-ai/grok-3-beta",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ],
    "max_tokens": 256
  }),
});
console.log(await r.json());

Request (JSON)

{
  "model": "x-ai/grok-3-beta",
  "messages": [
    {
      "role": "user",
      "content": "Hello!"
    }
  ],
  "max_tokens": 256
}

Response (JSON)

{
  "id": "chatcmpl-...",
  "object": "chat.completion",
  "model": "x-ai/grok-3-beta",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "Hi! How can I help?"
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 9,
    "completion_tokens": 12,
    "total_tokens": 21
  }
}

The address is taken from the provider's model list; check it against the provider's documentation.

Provider's API documentation

Source: AI Rate Card, https://airatecard.com/en/c/offer%3Afastrouter%7Cx-ai/grok-3-beta, prices checked 2026-11-04; seller's page: https://fastrouter.ai/models/x-ai/grok-3-beta

Technical details

ID: offer:fastrouter|x-ai/grok-3-beta