> For the complete documentation index, see [llms.txt](https://docs.tiun.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tiun.io/sdk/getting-started/readme.md).

# Overview

The tiun SDK is a lightweight JavaScript package that lets you integrate payments, subscriptions, and access control into any website or app.

{% hint style="info" %}
**NPM:** [@tiun/sdk](https://www.npmjs.com/package/@tiun/sdk)
{% endhint %}

## When to use the SDK

Use the tiun SDK when you need to:

* **Accept payments** — Open a checkout flow and let users purchase products or subscriptions directly from your site.
* **Control access** — Gate content behind a paywall, whether time-based or subscription-based.
* **Manage user sessions** — Let users log in, log out, and persist their session across visits.

The SDK runs entirely on the client side. Install it via npm, call `init()` once, and you're ready to go — no server-side code or manual script tags required.

{% hint style="info" %}
Ready to get started? Head to [Installation](/sdk/getting-started/installation.md) to add the SDK to your project.
{% endhint %}


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