OpenAI: GPT-5.1 Codex Max
openai/gpt-5.1-codex-max
Access GPT-5.1 Codex Max from OpenAI 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: "openai/gpt-5.1-codex-max"
}).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: "openai/gpt-5.1-codex-max"
}).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="openai/gpt-5.1-codex-max",
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": "openai/gpt-5.1-codex-max",
"messages": [
{"role": "user", "content": "Explain quantum computing in simple terms"}
]
}'
Model Card
GPT-5.1 Codex Max is OpenAI's frontier agentic coding model built for long-running, detailed work using context compaction. It's the first model trained to operate across multiple context windows coherently.
Context Window 400K
tokens
Max Output 128K
tokens
Input Cost $1.25
per million tokens
Output Cost $10
per million tokens
Release Date Oct 1, 2025
Model Playground
Try GPT-5.1 Codex Max instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
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ChatGPT-5.4 Nano
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ChatGPT-5.4
GPT-5.4 is OpenAI's latest frontier model released on March 5, 2026, designed for complex professional work with a 1.05M token context window, built-in computer-use capabilities, and improved coding from GPT-5.3-Codex. It is 33% less likely to make factual errors per claim compared to GPT-5.2 and scores 83% on OpenAI's GDPval knowledge work benchmark.
Frequently Asked Questions
You can access GPT-5.1 Codex Max by OpenAI 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 GPT-5.1 Codex Max 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 | $1.25 |
| Output | $10 |
GPT-5.1 Codex Max was created by OpenAI and released on Oct 1, 2025.
GPT-5.1 Codex Max supports a context window of 400K tokens. For reference, that is roughly equivalent to 800 pages of text.
GPT-5.1 Codex Max can generate up to 128K tokens in a single response.
Yes — the GPT-5.1 Codex Max 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 GPT-5.1 Codex Max to your app without worrying about API keys or setup.
Read the Docs View Tutorials