> ## Documentation Index > Fetch the complete documentation index at: https://www.twicecommerce.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # Custom Scripts > Inject analytics and third-party scripts into your storefront's head, with built-in security controls. Custom scripts editor showing external and inline script entries The Custom scripts page lets you add scripts to the `` of your storefront — for analytics, tag managers, chat widgets, or other third-party tools. Each script is sanitised on the server before it is saved. Scripts run on your live storefront with access to the page. Only add code from sources you trust. ## Script types You can add two kinds of script: | Type | What it is | Fields | | ------------ | -------------------------------------- | ----------------------------------------------------------------- | | **External** | Loads a script from a URL | `src`, optional `async`, `defer`, and a set of allowed attributes | | **Inline** | Runs script content you paste directly | `content` | ### Examples ```html External script (rendered in storefront head) theme={null} ``` ```javascript Inline script (paste the JavaScript only) theme={null} window.dataLayer = window.dataLayer || []; function gtag() { dataLayer.push(arguments); } gtag('js', new Date()); gtag('config', 'G-XXXXXXX'); ``` External scripts render as a `