xAI: Grok Code Fast 1
x-ai/grok-code-fast-1
Access Grok Code Fast 1 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-code-fast-1"
}).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-code-fast-1"
}).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-code-fast-1",
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-code-fast-1",
"messages": [
{"role": "user", "content": "Explain quantum computing in simple terms"}
]
}'
Model Card
Grok Code Fast 1 is a speedy, economical reasoning model built from scratch specifically for agentic coding workflows, released August 2025. It excels at TypeScript, Python, Java, Rust, C++, and Go with a 256K context window and ~92 tokens/second throughput.
Context Window 256K
tokens
Max Output 256K
tokens
Input Cost $0.2
per million tokens
Output Cost $1.5
per million tokens
Input text
modalities
Tool Use Yes
Knowledge Cutoff Oct 2023
Release Date Aug 28, 2025
Model Playground
Try Grok Code Fast 1 instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
Benchmarks
How Grok Code Fast 1 performs on standard evaluations.
| Benchmark | Score |
|---|---|
| GPQA Diamond Graduate-level science Q&A | 72.7% |
| Humanity's Last Exam Cross-domain reasoning | 7.5% |
| LiveCodeBench Recent coding problems | 65.7% |
| SciCode Scientific programming | 36.2% |
| AIME 2025 Advanced math exam | 43.3% |
| IFBench Instruction following | 41.4% |
| LCR Long-context reasoning | 48.3% |
| Terminal-Bench Hard Agentic terminal tasks | 17.4% |
| τ²-Bench Tool use / agents | 75.7% |
Scores sourced from Artificial Analysis.
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ImageGrok Imagine Image
Grok Imagine Image is xAI's standard text-to-image generation model, built on Aurora — an autoregressive Mixture-of-Experts architecture trained on billions of text-image pairs. It accepts text prompts and optional reference images as input, producing up to 10 images per request at 1K (1024×1024) or 2K (2048×2048) resolution across 13 aspect ratios. Output formats include JPEG, PNG, and WebP. The model is noted for strong instruction following, handling style transfer, object addition or removal, and multi-reference composition through natural language alone. It generates images quickly, making it practical for high-volume pipelines. Best suited for product mockups, marketing visuals, social media graphics, and concept art prototyping where speed and prompt adherence matter. A higher-quality variant, Grok Imagine Image Pro, is available when output fidelity is the priority.
ImageGrok Imagine Image (Quality)
Grok Imagine Image (Quality) is xAI's high-fidelity text-to-image generation model, built on the Aurora autoregressive Mixture-of-Experts architecture rather than a diffusion backbone. It targets applications where output quality is the priority over speed — delivering more natural lighting, richer textures, and cinematic consistency compared to standard-tier image models. Text rendering in generated images is notably legible across multiple languages, addressing a historically weak area for generative image models. The API supports 1K and 2K resolutions, 13 aspect ratios, and JPEG, PNG, and WebP outputs. Up to four image candidates can be generated per request. At $0.05 per image, it is well suited for product visuals, marketing assets, brand imagery, and creative workflows that require production-ready quality.
Frequently Asked Questions
You can access Grok Code Fast 1 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 Code Fast 1 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 | $1.5 |
Grok Code Fast 1 was created by xAI and released on Aug 28, 2025.
Grok Code Fast 1 supports a context window of 256K tokens. For reference, that is roughly equivalent to 512 pages of text.
Grok Code Fast 1 can generate up to 256K tokens in a single response.
Grok Code Fast 1 has a knowledge cutoff date of Oct 2023. This means the model was trained on data available up to that date.
Grok Code Fast 1 accepts the following input types: text. It produces: text.
Yes, Grok Code Fast 1 supports tool use (function calling), allowing it to interact with external tools, APIs, and data sources as part of its response flow.
Grok Code Fast 1 scores 21.6 on the Artificial Analysis Intelligence Index, outperforming 64% of tracked models. On math, it scores 43.3 (outperforms 44% of models).
Yes — the Grok Code Fast 1 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 Code Fast 1 to your app without worrying about API keys or setup.
Read the Docs View Tutorials