IconVault's Notification Builder uses the real `Notification` API: walk the permission flow (default, granted, denied), compose title, body and every option (icon, badge, image, tag, actions, vibration, silent), then fire real notifications that appear in your OS notification center, with action clicks logged back in the page. It is free and runs fully in your browser.

You will learn the rules that keep notifications trustworthy: they require permission and a secure context, most browsers only allow them from a user gesture or an installed context, and tags replace duplicates instead of stacking. The lab covers service-worker notifications for background delivery, why actions need careful labels, and the etiquette of never asking for permission on page load.