Definition

renotify (Notification option)

Short definition

renotify is a boolean option, e.g. { tag: "order-42", renotify: true }, that only has an effect when combined with tag. Without renotify, a new notification that replaces an existing same-tag notification updates silently with no new sound or vibration; with renotify: true, the replacement alerts the user exactly as a brand-new notification would.

Reviewed August 5, 2026

The spec requires tag to be set for renotify to do anything — passing renotify: true without a tag has no observable effect since there is nothing to "re-notify" in place of.

This is useful for status updates that genuinely warrant re-alerting, such as "Your order has shipped" replacing an earlier "Order confirmed" notification under the same tag, versus a live chat message-count bump that should not buzz the phone repeatedly.

Overusing renotify defeats the purpose of tag-based grouping in the first place, since the user experiences the same repeated interruption a stack of untagged notifications would cause.

Support and exact behaviour are documented alongside the rest of the Notification options on MDN: https://developer.mozilla.org/en-US/docs/Web/API/Notification/renotify.

Related terms

tag (Notification option)

tag is a string option, e.g. showNotification("New message", { tag: "chat-thread-42" }), used to identify a class of related notifications. When a new notification arrives with a tag matching one already showing, the browser replaces it in place by default rather than adding a second, separate notification to the shade.

actions (Notification option)

actions is an array option passed to showNotification(), e.g. { actions: [{ action: "reply", title: "Reply" }, { action: "dismiss", title: "Dismiss" }] }, that renders extra buttons on the notification itself. The service worker's notificationclick handler reads event.action to see which button, if any, the user pressed.

silent (Notification option)

silent is a boolean Notification option, e.g. showNotification("Synced", { silent: true }), that suppresses the sound, vibration and screen-wake behaviour a notification would normally trigger, while still adding it to the notification shade for the user to see whenever they next check.

requireInteraction (Notification option)

requireInteraction is a boolean option, e.g. showNotification("Incoming call", { requireInteraction: true }), that prevents the browser from automatically dismissing the notification after its default timeout (a few seconds on most desktop platforms). The notification instead stays visible until the user clicks it, clicks an action, or closes it manually.

Notification permission states

Notification.permission returns one of three strings: "default" (the user has not yet decided, so the site may still call Notification.requestPermission() to ask), "granted" (the site may show notifications), or "denied" (the site is blocked from showing notifications and, critically, cannot re-prompt programmatically once denied).

Declarative Web Push

Declarative Web Push is a format where the push message payload itself is a JSON object describing the notification (title, body, icon, and so on) that the browser displays directly, rather than requiring a service worker's push event handler to run arbitrary JavaScript to call showNotification(). WebKit introduced it partly to allow more efficient and more private push delivery on iOS/Safari.