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xAIText Generation/v1/ai/chat

Grok 4.20

Access Grok 4.20 through one API key. xAI's flagship model with the largest context window.

xAI's flagship model. Industry-leading 2M token context window with strong reasoning, real-time knowledge, and competitive output pricing.

No credit card required. Takes 30 seconds.

2,400+

Developers

1.2M+

API calls served

100+

Endpoints

$0.01

Per call

Yep, that's it.

Try it live

Send a message and see Grok 4.20 respond in real time.

POST/v1/ai/chat

Maximum tokens in the response.

Real-time tokens

Hit "Send Request" to see the response

Context Window

2M tokens

Max Output

16K tokens

Input Price

$2.00 / 1M tokens

Output Price

$6.00 / 1M tokens

Strengths

2M token context
Strong reasoning
Real-time knowledge
Competitive pricing

Quick start

Copy this snippet and start making calls with Grok 4.20.

const res = await fetch('https://api.yepapi.com/v1/ai/chat', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "x-ai/grok-4.20",
    "messages": [
      {
        "role": "user",
        "content": "Explain API gateways in 2 sentences."
      }
    ],
    "maxTokens": 256
  }),
});
const { data } = await res.json();
console.log(data.message.content);

Why use Grok 4.20 through YepAPI?

One API key for all models — no separate accounts
OpenAI SDK compatible — just change the base URL
No monthly minimums — pay per token
Switch models with one line of code
Full provider passthrough — citations, search results, and all extras included
Streaming and non-streaming support on every model
Works with Cursor, Claude, LangChain, and any LLM tool
Unified billing across all providers

What developers say

Switched from SerpAPI and cut our SERP costs by 80%. Same data quality, way simpler billing.

Marcus T.

SEO Platform Founder

One API key for AI models, SERP data, and web scraping. Saved us from managing 4 separate providers.

Priya S.

Full-Stack Developer

The $5 free credit let us prototype our entire rank tracking feature before committing. No other API does that.

Jake R.

Indie Hacker

Frequently asked questions

xAI's flagship model. Industry-leading 2M token context window with strong reasoning, real-time knowledge, and competitive output pricing.

Input tokens cost $2.00 per 1M tokens and output tokens cost $6.00 per 1M tokens through YepAPI. No monthly minimums — you only pay for what you use.

Sign up for a free API key, then send requests to the /v1/ai/chat endpoint.

Grok 4.20 supports a 2M token context window with up to 16K output tokens per request.

Ready to use Grok 4.20?

$5 free credit on signup. No credit card required. Pay per call.

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