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Web App Manifest (PWA) Checker

Validate your Web App Manifest for PWA installability — name, icons (192 & 512), display, start_url, and colors — with a pass/fail checklist. Free.

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💡 What this checks

  • Finds your Web App Manifest (from a page's <link rel="manifest"> or a direct URL).
  • Validates the fields a Progressive Web App needs to be installable — name, icons (192 & 512), display, start_url.
  • Flags missing theme/background colors and maskable icons.

Free Web App Manifest (PWA) Checker

Validate your Web App Manifest for Progressive Web App readiness. Enter your site or manifest.json URL and get a checklist of the fields a PWA needs to be installable — name, icons (192 and 512), display, start_url, and colors — with clear pass/fail results. Free, no sign-up.

What is a Web App Manifest?

A Web App Manifest is a JSON file (usually manifest.json or a .webmanifest file) that describes your site as an app: its name, icons, colors, and how it should launch. It is the piece that lets a Progressive Web App be installed to a phone's home screen or a desktop, opening in its own window without browser chrome. Getting the manifest right is the first requirement for an installable PWA.

How the checker works

It finds and validates your manifest automatically:

  • Enter your site URL and it locates the <link rel="manifest"> reference.
  • Or paste your manifest.json URL directly.
  • It parses the JSON and checks each installability field.
  • You get a pass/fail verdict plus a ranked checklist of what to fix.

What a PWA manifest must include

For a browser to offer to install your app, the manifest needs the essentials:

  • name or short_name — the app's title.
  • icons — at least a 192×192 and a 512×512 PNG.
  • display — set to standalone (or fullscreen / minimal-ui) so it opens app-style.
  • start_url — the page the app opens to.
  • Served over HTTPS — required for PWAs (except on localhost).

Icons: sizes and maskable

Icons are the field people most often get wrong. Browsers require both a 192×192 icon (for the home screen) and a 512×512 icon (for the splash screen and higher-density displays). Beyond that, add a 'maskable' icon — one with safe padding around the artwork — so Android can crop it into its various adaptive icon shapes without cutting off your logo. Providing PNG icons at these sizes is the single biggest step toward an installable app.

The manifest is necessary but not sufficient

A valid manifest is required for installability, but it is not the whole story. A full Progressive Web App also needs to be served over HTTPS and to register a service worker — the script that enables offline support and caching. This tool validates the manifest itself, which is the part most commonly misconfigured; once it passes, verify the service worker and HTTPS, and test the final result in Chrome DevTools under Application → Manifest.

Pro tip

Add theme_color and background_color so the app's toolbar and launch splash screen match your brand, and include a short description for app listings. Keep start_url pointing at a fast, meaningful landing page, and set scope so navigation stays within your app. To confirm the manifest is served with sensible caching, pair this with our Cache-Control Header Checker.

FAQ

Is this PWA manifest checker free?
Yes. It is completely free and requires no account or sign-up. Enter your site or manifest URL to validate it instantly.
What makes a PWA installable?
At minimum: a manifest with a name (or short_name), 192×192 and 512×512 icons, a display mode of standalone/fullscreen/minimal-ui, a start_url, HTTPS, and a registered service worker.
Why do I need both 192 and 512 pixel icons?
The 192×192 icon is used on the home screen and the 512×512 icon on the splash screen and high-density displays. Browsers require both for installability.
What is a maskable icon?
A maskable icon has extra safe padding so Android can crop it into different adaptive icon shapes without cutting off your logo. Add one with purpose set to 'maskable'.
Where should the manifest file live?
Anywhere on your site, referenced from your pages with <link rel="manifest" href="/manifest.json">. Serve it over HTTPS. This tool follows that link automatically.
Does a valid manifest alone make my site a PWA?
No. You also need HTTPS and a registered service worker for offline support. The manifest is the part most often misconfigured, which is what this tool validates.
Why can't the tool find my manifest?
The page may not include a <link rel="manifest"> tag, or it may be blocked. Enter the page that references the manifest, or paste the manifest.json URL directly.

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Pro tip: pair this tool with PageSpeed Insights Checker and View Source Code for a faster SEO workflow.