coderef

beforeinstallpromptLimited availability

The beforeinstallprompt event fires when a Progressive Web App (PWA) is installable. You can cancel the event and later call event.prompt() to control when the installation prompt is shown. The appinstalled event fires when the PWA is successfully installed.

Not yet supported in all major browsers — check the table and provide a fallback.

How to use ↓Compare browsers

Browser support

DesktopChrome
1–75Not supported
76+Supportedsince Jul 30, 2019
Current: 155
Edge
12–18Not supported
79+Supportedsince Jan 15, 2020
Current: 154
Firefox
✕Not supportedup to 157
Current: 157
Safari
✕Not supportedup to 27
Current: 27
MobileChrome Android
18–75Not supported
76+Supportedsince Jul 30, 2019
Current: 155
Firefox Android
✕Not supportedup to 157
Current: 157
Safari iOS
✕Not supportedup to 27
Current: 27

How to use

Not supported in Firefox, Safari, Firefox Android, Safari iOS. Use feature detection below and provide a fallback (or a polyfill) for those browsers.

Example

Full syntax and examples are on MDN: BeforeInstallPromptEvent.

Feature detection

JS · check before using
if ("BeforeInstallPromptEvent" in globalThis) {
  // BeforeInstallPromptEvent is available
} else {
  // load a polyfill or use a fallback
}

Documentation (MDN)

Specification

Sub-features

Support for each part of the feature (7). The overall table above shows when the whole feature works.

Sub-featureChromeEdgeFirefoxSafariChrome AndroidFirefox AndroidSafari iOS
BeforeInstallPromptEvent4479✕✕44✕✕
BeforeInstallPromptEvent.BeforeInstallPromptEvent4479✕✕44✕✕
BeforeInstallPromptEvent.platforms4479✕✕44✕✕
BeforeInstallPromptEvent.prompt7679✕✕76✕✕
BeforeInstallPromptEvent.userChoice4479✕✕44✕✕
Window.appinstalled_event6479✕✕57✕✕
Window.beforeinstallprompt_event6179✕✕61✕✕