Nous: Hermes 4 405B API

Access Nous: Hermes 4 405B from Nous Research using Puter.js AI API.

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Model Card

Hermes 4 405B is a frontier hybrid-mode reasoning model based on Llama-3.1-405B, trained on a 60B token dataset with verified reasoning traces. It features toggleable deep reasoning via think tags, massive improvements in math, code, STEM, and logic, and achieves state-of-the-art on RefusalBench for reduced censorship.

Context Window N/A

tokens

Max Output N/A

tokens

Input Cost $1

per million tokens

Output Cost $3

per million tokens

Release Date Aug 6, 2025

 

API Usage Example

Add Nous: Hermes 4 405B 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: "nousresearch/hermes-4-405b"
}).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: "nousresearch/hermes-4-405b"
        }).then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>

View full documentation →

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Frequently Asked Questions

What is this Nous: Hermes 4 405B API about?

The Nous: Hermes 4 405B API gives you access to Nous Research's chat model through Puter.js. With just a few lines of JavaScript, you can integrate Nous: Hermes 4 405B into any web app or Node.js project — no API keys, no backend, and no configuration required.

Who created Nous: Hermes 4 405B?

Nous: Hermes 4 405B was created by Nous Research and released on Aug 6, 2025.

How much does it cost?
The Nous: Hermes 4 405B API is available through the User-Pays Model. As a developer, you can add the Nous: Hermes 4 405B API to your app for free — your users pay for their own AI costs directly.
Price per 1M tokens
Input$1
Output$3
How do I access the Nous: Hermes 4 405B API?

You can access the Nous: Hermes 4 405B 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 Nous: Hermes 4 405B API work with React / Vue / Vanilla JS / Node / etc.?

Yes — the Nous: Hermes 4 405B 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 Nous: Hermes 4 405B to your app without worrying about API keys or setup.

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