GPT-5 Codex API

Access GPT-5 Codex from OpenAI using Puter.js AI API.

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Model Card

GPT-5 Codex is a version of GPT-5 optimized for agentic coding tasks in Codex or similar environments. It's designed for software engineering workflows with enhanced code generation capabilities.

Context Window N/A

tokens

Max Output 128K

tokens

Input Cost $1.25

per million tokens

Output Cost $10

per million tokens

Release Date Jul 1, 2025

 

API Usage Example

Add GPT-5 Codex to your app with just a few lines of code.
No API keys, no backend, no configuration required.

// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';

puter.ai.chat("Explain quantum computing in simple terms", {
    model: "openai/gpt-5-codex"
}).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-codex"
        }).then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>

View full documentation →

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Frequently Asked Questions

What is this GPT-5 Codex API about?

The GPT-5 Codex API gives you access to OpenAI's chat model through Puter.js. With just a few lines of JavaScript, you can integrate GPT-5 Codex into any web app or Node.js project — no API keys, no backend, and no configuration required.

Who created GPT-5 Codex?

GPT-5 Codex was created by OpenAI and released on Jul 1, 2025.

What is the max output length of GPT-5 Codex?

GPT-5 Codex can generate up to 128K tokens in a single response.

How much does it cost?
The GPT-5 Codex API is available through the User-Pays Model. As a developer, you can add the GPT-5 Codex API to your app for free — your users pay for their own AI costs directly.
Price per 1M tokens
Input$1.25
Output$10
How do I access the GPT-5 Codex API?

You can access the GPT-5 Codex API with just a few lines of JavaScript — no API keys, no backend, and no configuration required. Include the Puter.js library in your project and start making calls right away. For more details, check out our documentation.

Does the GPT-5 Codex API work with React / Vue / Vanilla JS / Node / etc.?

Yes — the GPT-5 Codex 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 Codex to your app without worrying about API keys or setup.

Read the Docs View Tutorials