xAI: Grok 4.20 Beta

This model is no longer available.

Add AI to your application with Puter.js.

Explore Other Models

Model Card

Grok 4.20 Beta is xAI's newest flagship model, featuring a native 4-agent collaboration system (Grok, Harper, Benjamin, Lucas) that reasons in parallel and debates internally before delivering a unified response. It introduces a rapid-learning architecture that improves weekly from real-world feedback, and builds on a ~3T parameter MoE backbone with up to 2M token context. It claims a 65% reduction in hallucinations over Grok 4.1 and strong gains in coding, math, and engineering reasoning.

Context Window 2M

tokens

Max Output 256K

tokens

Input Cost $2

per million tokens

Output Cost $6

per million tokens

Release Date Mar 12, 2026

 

Code Example

Add AI to your app with the Puter.js AI API — no API keys or setup required.

// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';

puter.ai.chat("Explain quantum computing in simple terms").then(response => {
    document.body.innerHTML = response.message.content;
});

<html>
<body>
    <script src="https://js.puter.com/v2/"></script>
    <script>
        puter.ai.chat("Explain quantum computing in simple terms").then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>

More AI Models From xAI

Find other xAI models →

Chat

Grok 4.20

Grok 4.20 is xAI's flagship large language model, offering a rare combination of low hallucination rates and high throughput at competitive pricing. It achieved a record 78% non-hallucination rate on the Artificial Analysis Omniscience benchmark — the highest of any model tested — making it a strong choice for applications where factual reliability matters more than peak reasoning scores. It scored 78.5% on GPQA Diamond and 87.3% on MATH-500. The model supports a 2M-token context window, text and image inputs, parallel function calling, structured outputs, and built-in web search. Reasoning can be toggled on or off per request via API parameter. At $2 per million input tokens and $6 per million output tokens, it's one of the most affordable frontier models available, with output speeds exceeding 230 tokens per second.

 Chat

Grok 4.20 Multi-Agent

Grok 4.20 Multi-Agent is a variant of xAI's Grok 4.20 purpose-built for orchestrating multiple AI agents that collaborate on complex, multi-step tasks in real time. Rather than relying on a single inference pass, it coordinates parallel agents that independently search, analyze, and cross-reference information before synthesizing a final response. At low or medium reasoning effort it runs 4 agents; at high or extra-high effort it scales to 16. It scored a 68.7 agentic index on Artificial Analysis — among the highest available. The model shares Grok 4.20's 2M-token context window and natively supports web search, X search, and tool orchestration. It generates up to 2M output tokens per response, making it well suited for deep research workflows, multi-source analysis, and long-running agent pipelines.

 Chat

Grok 4.1 Fast

Grok 4.1 Fast is xAI's best tool-calling model released November 2025, featuring a 2M context window and halved hallucination rates versus Grok 4 Fast. It comes in reasoning and non-reasoning modes and is optimized for agentic workflows with native support for web search, X search, and code execution.

Frequently Asked Questions

How do I use Grok 4.20 Beta?

You can access Grok 4.20 Beta by xAI through Puter.js AI API. Include the library in your web app or Node.js project and start making calls with just a few lines of JavaScript — no backend and no configuration required. You can also use it with Python or cURL via Puter's OpenAI-compatible API.

Is Grok 4.20 Beta free?

Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add Grok 4.20 Beta to your app at no cost — your users pay for their own AI usage directly, making it completely free for you as a developer.

What is the pricing for Grok 4.20 Beta?
Grok 4.20 Beta costs $2 per 1M input tokens and $6 per 1M output tokens.
Price per 1M tokens
Input$2
Output$6
Who created Grok 4.20 Beta?

Grok 4.20 Beta was created by xAI and released on Mar 12, 2026.

What is the context window of Grok 4.20 Beta?

Grok 4.20 Beta supports a context window of 2M tokens. For reference, that is roughly equivalent to 4,000 pages of text.

What is the max output length of Grok 4.20 Beta?

Grok 4.20 Beta can generate up to 256K tokens in a single response.

Does it work with React / Vue / Vanilla JS / Node / etc.?

Yes — the Grok 4.20 Beta API works with any JavaScript framework, Node.js, or plain HTML through Puter.js. Just include the library and start building. See the documentation for more details.

Get started with Puter.js

Add AI to your application without worrying about API keys or setup.

Explore Models View Tutorials