Answer

What are the requirements for the Chrome install prompt?

Short answer

Chrome fires beforeinstallprompt when the site is served over HTTPS, links a valid manifest with name, start_url and 192px + 512px icons, registers a service worker with a fetch handler, and passes a user-engagement heuristic (typically one interaction and ~30 seconds of use). Any failing criterion silently blocks the prompt.

By InstantPWA engineering·Reviewed July 7, 2026

The technical checklist

HTTPS. Manifest with name (or short_name), start_url, display "standalone" or "fullscreen", icons at 192px and 512px, background_color and theme_color. A registered service worker whose fetch handler responds to at least the start_url.

The engagement heuristic

Chrome requires a click or tap on the page and, historically, ~30 seconds of active use. This is why beforeinstallprompt often fires late — not on page load.

The suppression rules

If the user dismisses twice, Chrome backs off for 90 days. Testing tip: use a fresh incognito window per attempt.

Sources

web.dev — Installation criteria

What is a PWA?

A PWA (Progressive Web App) is a regular website that meets three technical criteria — HTTPS, a Web App Manifest and a service worker — so browsers let visitors install it on their home screen. Once installed, it launches like a native app, works offline and can send push notifications.

Why is my PWA install prompt not showing?

Chrome shows the install prompt only when the site passes strict installability criteria: HTTPS, a valid manifest with name, icons and start_url, a registered service worker with a fetch handler, and the user has not previously dismissed the prompt. Any one of these missing is enough to block the prompt entirely.