How to add custom code to a WordPress site

• Self-hosted: an administrator account. There is no plan requirement.
• WordPress.com: a plan that allows plugins, with hosting features activated. Free sites cannot use <script> tags.
• The script from your tool, as a complete <script> tag
• A theme that calls wp_head(), which is what prints head scripts on the front end

1. Check what your site allowsA self-hosted site can do this today. On WordPress.com, look at your plan first: script tags need a plugin-enabled plan and activated hosting features. WordPress.com’s own pages name the qualifying plans differently, so go by its current plan page.
2. Install a header and footer pluginWPCode is the one WordPress.com’s own guide uses. Install and activate it. The route is identical on self-hosted WordPress.
3. Paste the script into the Header boxGo to Code Snippets → Header & Footer. Paste the whole tag into the Header box and click Save Changes.

   <script defer src="https://example.com/tool.js"></script>

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4. Or print it from code with wp_headIf you would rather not add a plugin on a self-hosted site, hook the wp_head action. It prints into the head on the front end, and only when the theme calls wp_head().

   add_action( 'wp_head', function () {
       echo '<script defer src="https://example.com/tool.js"></script>';
   } );

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• Log out, or open the site in a private window, then view the page source and search for the script’s address.
• Reload with developer tools open on the Network tab and confirm the script is requested.

WordPress.com removes the script tag

The site is on a free plan or one without plugins. Move to a plan that allows plugins, activate hosting features, then add the script through WPCode.

The wp_head code prints nothing

The action fires only if the theme calls wp_head(). Look in the theme’s header template for that call, or switch to the plugin route.

The tag is in the source but the script loads late or never

A caching or optimisation plugin may be delaying, combining or stripping third-party scripts. Check its settings and exclude this script’s address.

Checked on 2026-11-11 against WordPress Developer Resources: wp_head hook, WordPress.com Support: Add code to headers, WordPress.com Support: Use code on your site.