How to include HTML tags like <sup> in WordPress post titles without issues?

[sofiap]

I have a WordPress website where I manage various products through a custom post type named ‘product’. I want to display the registered trademark symbol as superscript using ^{tags. However, when I add ^&reg; to the title, it doesn’t render correctly and instead shows the HTML code itself.}

I’ve attempted to use several HTML tags, but they all display as text rather than functioning correctly in the title, like <strong>, <em>, <b>, <i>, and also a CSS class with <span class="superscript"></span> that I created.

I wrote the following function:

function add_superscript_to_trademarks_in_single_title( $title ) {
    if ( is_singular('product') ) {
        $title = str_replace( array( '&reg;', '®' ), '<sup>&reg;</sup>', $title );
    } else {
        $title = wp_strip_all_tags($title);
    }
    return $title;
}
add_filter( 'the_title', 'add_superscript_to_trademarks_in_single_title' );

This code works well on individual product pages, but on archive pages, the HTML tags still appear as text. I’m using a self-hosted WordPress site with the Astra theme and the Custom Post Type UI plugin.

Is there a method to ensure that WordPress renders HTML properly in titles on all types of pages, including archives?

[livbrown]

WordPress uses different sanitization rules for different page types. Archive pages have stricter filtering that auto-escapes HTML entities. Don’t fight it - use CSS pseudo-elements instead. They’re way more reliable. Add this to your stylesheet: .trademark:after { content: '®'; vertical-align: super; font-size: 0.8em; } Then update your function to wrap trademark symbols with <span class="trademark"></span>. You’re just adding a CSS class, so it skips title sanitization completely. Looks exactly like superscript tags but works everywhere - archives, feeds, meta tags, wherever HTML would normally break.

[josephk]

WordPress sanitizes titles differently on archive pages - they strip HTML by default for security. You’ll need to hook into pre_get_posts or use a filter like single_post_title instead. I ran into this same thing with chemical formulas in titles. What worked for me was creating a custom function that runs earlier and uses wp_kses() with specific allowed tags. Add this to your functions.php: php function allow_html_in_titles($allowed, $context) { if ($context === 'post') { $allowed['sup'] = array(); } return $allowed; } add_filter('wp_kses_allowed_html', 'allow_html_in_titles', 10, 2); This tells WordPress that <sup> tags are safe. Then update your existing function to work on archive pages by removing the is_singular() condition.

[Alice45]

try using wp_kses_allowed_html() to let the ^{tag work in titles. by default, wp removes html for security, so make sure to allow it! also, check if you need to use the wp_title filter to fix text showing up raw.}