gvadev

Cal24h is an online booking platform that lets you publish event calendars, appointment forms, and catalogues. This plugin embeds any Cal24h organization or event on your WordPress site with just a shortcode or block, while offering a floating button modal for persistent calls to action.
Highlights
<ul>
<li>Gutenberg block with an inspector panel to configure organization, event, language, and appearance.</li>
<li>Shortcode <code>[cal24h]</code> supporting attributes for iframe or floating-button display modes.</li>
<li>Settings page (<code>Settings → Cal24h</code>) to define default values such as organization slug, event slug, language, and colors.</li>
<li>Theme personalization parameters for the stepper (primary colors, step labels, card backgrounds, stepper background).</li>
<li>Responsive floating button that opens a customizable modal overlay.</li>
<li>Ready-to-ship translations and language loading for both editor and front end. Included locales: ar, bn_BD, da_DK, de_DE, el, en_US, es_ES, fa_IR, fi, fr_FR, he_IL, hi_IN, id_ID, it_IT, ja, ko_KR, nb_NO, nl_NL, pa_IN, pt_BR, pt_PT, ru_RU, sv_SE, sw, tr_TR, ur, wo, zh_CN.</li>
<li>Paste-friendly slugs: you can paste a full Cal24h URL (e.g., <code>https://cal24h.com/integration/org/event</code>) into settings or shortcode attributes — the plugin extracts the correct organization/event automatically.</li>
</ul>

Cal24h

Embed the Cal24h booking experience in WordPress with a shortcode, Gutenberg block, or floating modal.

breely

Fill your schedule, grow your business. 
Breely is the most flexible platform allowing you build the exact appointment scheduling, forms, and workflows for your business.
Breely offers 1:1 appointment scheduling, group classes, workshops, and class series scheduling. 
You can also create forms, waivers, and more. This plugin allows you to embed the forms 
created in Breely into your WordPress site.

Breely

Embed Breely appointment booking and forms into your site.

Cal24h vs Breely