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Randozi
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Web App Manifest Checker

Chrome shows an install button only when the manifest has the right members. Paste yours and see exactly which ones are missing or wrong, before you wonder why nothing appears.

Install requirements (Chromium, per MDN)

1 to fix

HTTPS, the link from your page and the icon files themselves are not checked here.
  • Error: No 512×512 icon is declared.
  • Tip: No icon has purpose “maskable”. Android can crop an icon without it; a maskable icon keeps your artwork inside the safe area.
  • Tip: No scope. The default is the start_url with its file name, query and fragment removed; the specification advises setting it, preferably to “/”.
  • Tip: No background_color: the splash screen uses the browser default.
  • OK: Name: “Randozi”.
  • OK: start_url: /
  • OK: display: standalone
  • OK: A 192×192 icon is declared.

How it works

  1. Open your manifest.webmanifest or manifest.json and copy everything in it.
  2. Paste it into the box. It is checked as you type.
  3. Read the errors first: each one is a requirement that stops installation. Warnings are real mistakes that do not block it.
  4. Fix the file, paste it again and read the warnings and tips for the finishing touches.

What people use it for

  • Making a site installable

    Find the missing icon size or display value that keeps the install prompt away.

  • Reviewing a client's PWA

    Run a quick check on a manifest before spending time in browser dev tools.

  • Catching typos

    A wrong display value or a malformed icon size is easy to miss by eye.

Questions

Which requirements are checked?
The members that MDN lists for Chromium browsers (Chrome, Edge, Samsung Internet): a name or short_name, a start_url, a display or display_override member, a 192×192 and a 512×512 icon, and prefer_related_applications not set to true. Allowed values for display, orientation, dir and icon purpose come from the W3C manifest specification.
Does a green result guarantee an install button?
No. The page must also be served over HTTPS (or localhost), the manifest must be linked from the page and the icon files must really load. This tool reads only the text you paste, so it cannot see those. Other browsers have their own rules too.
Why only warnings or tips for scope and short_name?
They do not stop installation. Wrong values for orientation, dir, icon purpose or sizes are warnings too. The specification sets no length for short_name, so 12 characters is only a rule of thumb for how launchers cut names (a tip, not a warning). A start_url outside the scope makes the browser ignore your scope. The check on the start_url being inside the scope compares path prefixes.
Is my manifest uploaded?
No. It is parsed in your browser. Up to 200,000 characters.