xAI: Grok 3 Mini Fast
x-ai/grok-3-mini-fast
Access Grok 3 Mini Fast from xAI using Puter.js AI API.
Get Started// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';
puter.ai.chat("Explain quantum computing in simple terms", {
model: "x-ai/grok-3-mini-fast"
}).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", {
model: "x-ai/grok-3-mini-fast"
}).then(response => {
document.body.innerHTML = response.message.content;
});
</script>
</body>
</html>
# pip install openai
from openai import OpenAI
client = OpenAI(
base_url="https://api.puter.com/puterai/openai/v1/",
api_key="YOUR_PUTER_AUTH_TOKEN",
)
response = client.chat.completions.create(
model="x-ai/grok-3-mini-fast",
messages=[
{"role": "user", "content": "Explain quantum computing in simple terms"}
],
)
print(response.choices[0].message.content)
curl https://api.puter.com/puterai/openai/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer YOUR_PUTER_AUTH_TOKEN" \
-d '{
"model": "x-ai/grok-3-mini-fast",
"messages": [
{"role": "user", "content": "Explain quantum computing in simple terms"}
]
}'
Model Card
Grok 3 Mini Fast is the speed-optimized variant of Grok 3 Mini, running on faster infrastructure for significantly quicker response times. It provides identical reasoning quality to Grok 3 Mini but is designed for latency-sensitive applications.
Context Window 131K
tokens
Max Output 131K
tokens
Input Cost $0.6
per million tokens
Output Cost $4
per million tokens
Input text
modalities
Tool Use Yes
Knowledge Cutoff Nov 2024
Release Date Feb 17, 2025
Model Playground
Try Grok 3 Mini Fast instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
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Frequently Asked Questions
You can access Grok 3 Mini Fast 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.
Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add Grok 3 Mini Fast to your app at no cost — your users pay for their own AI usage directly, making it completely free for you as a developer.
| Price per 1M tokens | |
|---|---|
| Input | $0.6 |
| Output | $4 |
Grok 3 Mini Fast was created by xAI and released on Feb 17, 2025.
Grok 3 Mini Fast supports a context window of 131K tokens. For reference, that is roughly equivalent to 262 pages of text.
Grok 3 Mini Fast can generate up to 131K tokens in a single response.
Grok 3 Mini Fast has a knowledge cutoff date of Nov 2024. This means the model was trained on data available up to that date.
Grok 3 Mini Fast accepts the following input types: text. It produces: text.
Yes, Grok 3 Mini Fast supports tool use (function calling), allowing it to interact with external tools, APIs, and data sources as part of its response flow.
Yes — the Grok 3 Mini Fast 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 Grok 3 Mini Fast to your app without worrying about API keys or setup.
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