xAI: Grok 4 Fast Non-Reasoning
x-ai/grok-4-fast-non-reasoning
Access Grok 4 Fast Non-Reasoning 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-4-fast-non-reasoning"
}).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-4-fast-non-reasoning"
}).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-4-fast-non-reasoning",
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-4-fast-non-reasoning",
"messages": [
{"role": "user", "content": "Explain quantum computing in simple terms"}
]
}'
Model Card
Grok 4 Fast Non-Reasoning is the speed-optimized, non-reasoning variant of Grok 4 Fast that bypasses extended chain-of-thought for instant responses. It uses the same unified architecture with a 2M context window but skips deliberation, delivering up to 342 tokens/second throughput for high-volume, latency-sensitive applications.
Context Window 2M
tokens
Max Output 2M
tokens
Input Cost $0.2
per million tokens
Output Cost $0.5
per million tokens
Input text, image
modalities
Tool Use Yes
Knowledge Cutoff Jul 2025
Release Date Sep 19, 2025
Model Playground
Try Grok 4 Fast Non-Reasoning instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
Benchmarks
How Grok 4 Fast Non-Reasoning performs on standard evaluations.
| Benchmark | Score |
|---|---|
| GPQA Diamond Graduate-level science Q&A | 60.6% |
| Humanity's Last Exam Cross-domain reasoning | 5.0% |
| LiveCodeBench Recent coding problems | 40.1% |
| SciCode Scientific programming | 32.9% |
| AIME 2025 Advanced math exam | 41.3% |
| IFBench Instruction following | 37.7% |
| LCR Long-context reasoning | 20.0% |
| Terminal-Bench Hard Agentic terminal tasks | 12.1% |
| τ²-Bench Tool use / agents | 63.7% |
Scores sourced from Artificial Analysis.
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Frequently Asked Questions
You can access Grok 4 Fast Non-Reasoning 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 4 Fast Non-Reasoning 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 | $0.2 |
| Output | $0.5 |
Grok 4 Fast Non-Reasoning was created by xAI and released on Sep 19, 2025.
Grok 4 Fast Non-Reasoning supports a context window of 2M tokens. For reference, that is roughly equivalent to 4,000 pages of text.
Grok 4 Fast Non-Reasoning can generate up to 2M tokens in a single response.
Grok 4 Fast Non-Reasoning has a knowledge cutoff date of Jul 2025. This means the model was trained on data available up to that date.
Grok 4 Fast Non-Reasoning accepts the following input types: text, image. It produces: text.
Yes, Grok 4 Fast Non-Reasoning supports tool use (function calling), allowing it to interact with external tools, APIs, and data sources as part of its response flow.
Grok 4 Fast Non-Reasoning scores 16.5 on the Artificial Analysis Intelligence Index, outperforming 55% of tracked models. On math, it scores 41.3 (outperforms 42% of models).
Yes — the Grok 4 Fast Non-Reasoning 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 4 Fast Non-Reasoning to your app without worrying about API keys or setup.
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