GPT-5.1 Codex Mini API

Access GPT-5.1 Codex Mini from OpenAI using Puter.js AI API.

Get Started

Model Card

GPT-5.1 Codex Mini is a smaller, more cost-effective version of GPT-5.1 Codex providing approximately 4x more usage within subscription limits. It balances coding capability with efficiency.

Context Window N/A

tokens

Max Output 128K

tokens

Input Cost $0.25

per million tokens

Output Cost $2

per million tokens

Input text, image

modalities

Tool Use Yes

 

Knowledge Cutoff Sep 30, 2024

 

Release Date Nov 13, 2025

 

API Usage Example

Add GPT-5.1 Codex Mini 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-5.1-codex-mini"
}).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-mini"
        }).then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>

View full documentation →

More Models from OpenAI

Chat

GPT-5.4

GPT-5.4 is OpenAI's latest frontier model released on March 5, 2026, designed for complex profession...

 Chat

GPT-5.4 Pro

GPT-5.4 Pro is a higher-compute version of GPT-5.4 that allocates more reasoning time to produce sma...

 Chat

GPT-5.3 Chat

GPT-5.3 Chat is OpenAI's latest conversational model update (also known as GPT-5.3 Instant), designe...

View all OpenAI models →

Frequently Asked Questions

What is this GPT-5.1 Codex Mini API about?

The GPT-5.1 Codex Mini API gives you access to OpenAI's chat model through Puter.js. With just a few lines of JavaScript, you can integrate GPT-5.1 Codex Mini into any web app or Node.js project — no API keys, no backend, and no configuration required.

Who created GPT-5.1 Codex Mini?

GPT-5.1 Codex Mini was created by OpenAI and released on Nov 13, 2025.

What is the max output length of GPT-5.1 Codex Mini?

GPT-5.1 Codex Mini can generate up to 128K tokens in a single response.

What is the knowledge cutoff of GPT-5.1 Codex Mini?

GPT-5.1 Codex Mini has a knowledge cutoff date of Sep 30, 2024. This means the model was trained on data available up to that date.

What types of input can GPT-5.1 Codex Mini process?

GPT-5.1 Codex Mini accepts the following input types: text, image. It produces: text.

Does GPT-5.1 Codex Mini support tool use (function calling)?

Yes, GPT-5.1 Codex Mini supports tool use (function calling), allowing it to interact with external tools, APIs, and data sources as part of its response flow.

How much does it cost?
The GPT-5.1 Codex Mini API is available through the User-Pays Model. As a developer, you can add the GPT-5.1 Codex Mini API to your app for free — your users pay for their own AI costs directly.
Price per 1M tokens
Input$0.25
Output$2
How do I access the GPT-5.1 Codex Mini API?

You can access the GPT-5.1 Codex Mini 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-5.1 Codex Mini API work with React / Vue / Vanilla JS / Node / etc.?

Yes — the GPT-5.1 Codex Mini 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 Mini to your app without worrying about API keys or setup.

Read the Docs View Tutorials