x-ai/grok-4-1-fast
Model Card
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.
Context Window
N/A
tokens
Max Output
2M
tokens
Input Cost
$0.2
per million tokens
Output Cost
$0.5
per million tokens
Release Date
Nov 19, 2025
API Usage Example
Add xAI: Grok 4.1 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-4-1-fast"
}).then(response => {
document.body.innerHTML = response.message.content;
});
</script>
</body>
</html>
Get started with Puter.js
Add xAI: Grok 4.1 Fast to your app without worrying about API keys or setup.
Read the Docs View Tutorials