Definition

Lighthouse PWA audit

Short definition

The Lighthouse PWA audit, run from Chrome DevTools' Lighthouse panel or the lighthouse CLI, checks a page against Chromium's installability criteria — valid manifest fields, icon sizes, registered service worker, HTTPS — and flags exactly which checks pass or fail, rather than giving a single opaque score for the category.

Reviewed August 10, 2026

Historically Lighthouse gave PWAs a dedicated 0-100 score category; that scoring was removed in favor of a pass/fail checklist view, since installability is fundamentally binary (either the criteria are met or they are not) rather than something meaningfully gradient like performance.

Running it from the CLI, e.g. npx lighthouse https://example.com --only-categories=pwa --output=json, is the standard way to include the check in CI so a regression (like an icon file accidentally deleted from the manifest's icons list) fails a build rather than shipping silently.

The audit only reflects what Lighthouse can observe from a single automated page load — it does not verify actual push notification delivery, real device install behaviour, or iOS-specific flows, since Lighthouse runs on a Chromium engine only.

Full documentation of the current checks lives at https://developer.chrome.com/docs/lighthouse/pwa/.

Related terms

PWA install criteria

Chromium's PWA install criteria require: the site served over HTTPS; a linked Web App Manifest with at least a name (or short_name), a 192x192 and 512x512 icon, a start_url, and a display value of standalone, fullscreen, minimal-ui or a display_override entry; and a registered service worker with a fetch event handler, even a minimal pass-through one.

Web App Manifest

A Web App Manifest is a JSON file (usually manifest.webmanifest) that declares your app's name, icons, start URL, theme colour and display mode. The browser reads it to render the install prompt and the home-screen icon.

screenshots (manifest field)

screenshots is a manifest array such as [{"src": "/shots/home.png", "sizes": "1080x1920", "type": "image/png", "form_factor": "narrow"}] used to render a richer install UI with app previews, similar to a Play Store listing, instead of the plain one-line install banner.

display-mode media query

display-mode is a CSS media feature, usable both in stylesheets (@media (display-mode: standalone) { ... }) and in JavaScript via window.matchMedia("(display-mode: standalone)").matches, that reports which of browser, minimal-ui, standalone or fullscreen is currently applied to the page — regardless of what the manifest requested, since the OS can downgrade the requested mode.

beforeinstallprompt userChoice

userChoice is a property on the deferred beforeinstallprompt event, resolving to an object like { outcome: "accepted" | "dismissed", platform: "web" }, available after calling deferredEvent.prompt(). It is the only reliable, synchronous-feeling signal for whether a user actually accepted or dismissed your custom install prompt in that specific interaction.

Service worker

A service worker is a JavaScript file the browser runs in the background, separate from the page. It intercepts network requests, caches responses so the site works offline, and receives web-push events so the site can notify the user when it is closed.