Blog

GPT-5.1-Codex-Max Is Now Available in Puter.js

On this page

Puter.js now supports GPT-5.1-Codex-Max, OpenAI's most powerful code generation model. Add it to your application for free without needing an OpenAI developer account or API key.

What is GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max is OpenAI's flagship code generation model designed for the most demanding coding tasks. It excels at complex code generation, debugging, code explanation, and software architecture.

Examples

Code Generation

puter.ai.chat(
    "Write a Python function that implements a binary search tree with insert, delete, and search operations",
    { model: "openrouter:openai/gpt-5.1-codex-max" }
)

Code Debugging

puter.ai.chat(
    "Find and fix the bug in this code:\n\nfunction fibonacci(n) {\n  if (n <= 1) return n;\n  return fibonacci(n - 1) + fibonacci(n - 1);\n}",
    { model: "openrouter:openai/gpt-5.1-codex-max" }
)

Code Explanation

puter.ai.chat(
    "Explain this regex pattern and what it matches: ^(?=.*[A-Z])(?=.*[a-z])(?=.*\\d)[A-Za-z\\d]{8,}$",
    { model: "openrouter:openai/gpt-5.1-codex-max" }
)

Other Codex Models

In addition to Codex Max, Puter.js also supports other Codex variants:

Model Best For
openrouter:openai/gpt-5.1-codex-max Complex coding tasks requiring maximum capability
openrouter:openai/gpt-5.1-codex Balanced performance for everyday coding tasks
openrouter:openai/gpt-5.1-codex-mini Fast responses for simpler code generation

Using GPT-5.1-Codex

puter.ai.chat(
    "Write a function to validate email addresses",
    { model: "openrouter:openai/gpt-5.1-codex" }
)

Using GPT-5.1-Codex-Mini

puter.ai.chat(
    "Write a function to reverse a string",
    { model: "openrouter:openai/gpt-5.1-codex-mini" }
)

Get Started Now

Just add one script tag to your HTML:

<script src="https://js.puter.com/v2/"></script>

No API keys or OpenAI developer account needed. Start building with Codex immediately.

Learn more:

Free, Serverless AI and Cloud

Start creating powerful web applications with Puter.js in seconds!

Get Started Now

Read the Docs Try the Playground