Grok 3 Fast API

Access Grok 3 Fast from xAI using Puter.js AI API.

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Model Card

Grok 3 Fast is a latency-optimized variant of Grok 3 using the same underlying model but served on faster infrastructure. It delivers quicker response times for latency-sensitive applications while maintaining equivalent reasoning quality and 131K context window.

Context Window

131K

tokens

Max Output

131,072

tokens

Input Cost

$5

per million tokens

Output Cost

$25

per million tokens

API Usage Example

Add Grok 3 Fast to your app with just a few lines of code.
No API keys, no backend, no configuration required.

<html>
<body>
    <script src="https://js.puter.com/v2/"></script>
    <script>
        puter.ai.chat("Explain quantum computing in simple terms", {
            model: "x-ai/grok-3-fast"
        }).then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>

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Get started with Puter.js

Add Grok 3 Fast to your app without worrying about API keys or setup.

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