Change WordPress Widget Title From h2 to h4

Many WordPress themes wrap widget titles in an h2, which clutters the heading outline of a page with sidebar headings at the same level as the content. This snippet changes the WordPress widget title tag from h2 to h4, or any tag you choose, in every sidebar.

The theme’s classes stay on the heading and the title text is left exactly as typed, spaces and punctuation included.

The snippet

<?php
/**
 * Change the heading tag of WordPress widget titles, for example from h2 to h4.
 */

// ===== Config =====
function dpc_widget_title_tag() {
	return 'h4'; // h1 to h6, p, span or div.
}
// ===== End of config =====

add_filter( 'dynamic_sidebar_params', 'dpc_widget_title_tag_params' );

function dpc_widget_title_tag_params( $params ) {
	$tag     = strtolower( (string) dpc_widget_title_tag() );
	$allowed = array( 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'p', 'span', 'div' );

	if ( ! in_array( $tag, $allowed, true ) || empty( $params[0] ) || ! is_array( $params[0] ) ) {
		return $params;
	}

	// Swap only the heading tag the sidebar wraps the title in; classes and the title stay.
	foreach ( array( 'before_title', 'after_title' ) as $key ) {
		if ( isset( $params[0][ $key ] ) && is_string( $params[0][ $key ] ) ) {
			$params[0][ $key ] = preg_replace( '#<(/?)h[1-6](?=[\s>])#i', '<$1' . $tag, $params[0][ $key ] );
		}
	}

	return $params;
}

How it works

Each sidebar defines the HTML around widget titles in before_title and after_title when it is registered, for example <h2 class="widget-title"> and </h2>.
Before each widget is printed, dynamic_sidebar() passes those settings through the dynamic_sidebar_params filter. The snippet swaps the heading tag there, so the widget prints <h4 class="widget-title"> around its title.
Only h1 to h6 tags are replaced, and the tag from the config is checked against a short allow list, so a typo cannot break the markup.

The older version of this post used the widget_title filter and a regex that removed every space and special character from titles, so “Recent Posts” became “RecentPosts”, and it put an h4 inside the theme’s h2.

Add it with Scripts Organizer

In Scripts Organizer go to Code Blocks → Add New and give the block a name. Set Trigger location to Everywhere, tick PHP under Script location, paste the code into the PHP editor and publish. Leave Action/Hook empty. Sidebars are rendered on the front end, where Everywhere code is loaded before dynamic_sidebar() runs.

The same code also works unchanged in a small plugin or an mu-plugin.

Customise it

Another tag: return 'h3', 'p' or 'span' from dpc_widget_title_tag().
One sidebar only: at the start of dpc_widget_title_tag_params(), return early unless $params[0]['id'] is that sidebar’s ID.
Register your own sidebar with the tag you want from the start: see Register a WordPress Sidebar for Oxygen Builder.
Hide titles on some pages: see Remove Widget Title Conditionally.

Gotchas

Block widgets have no widget title; a Heading block inside them keeps the level you pick in the editor.
Widgets printed with the_widget() instead of a sidebar do not pass through dynamic_sidebar_params.
Theme CSS that targets .widget h2 no longer matches; target .widget-title instead.

In the Scripts Organizer library Import it with one click from Scripts Organizer.