site.webmanifest Checker
Validate a web app manifest, inspect its important fields, and get practical fixes for common JSON, icon, URL, display and color problems.
Check your manifest
A direct manifest URL works when the server allows browser access. Some websites block cross-origin checks; paste the JSON below when that happens.
Important: this checks the manifest file itself. A fully installable PWA may also require HTTPS, suitable icons, browser-specific criteria, and a working service worker.
What this checker examines
| Field | What it checks |
|---|---|
name / short_name | Whether the app has a usable full or compact name. |
start_url | Whether an app launch URL is present and formatted as a string. |
display | Whether the display mode is a recognized value such as standalone. |
icons | Whether icon entries contain source URLs and useful sizes, including 192×192 and 512×512 recommendations. |
| Colors | Whether theme_color and background_color resemble valid CSS colors. |
id, scope, description | Whether useful modern manifest members are present. |
How to add a manifest to a website
Save the JSON file as site.webmanifest or manifest.webmanifest, then add this line inside the page's <head>:
<link rel="manifest" href="/site.webmanifest">Serve .webmanifest files with the application/manifest+json media type when your hosting configuration allows it.
Need a manifest?
Use the Web App Manifest Generator to create and download a clean starter file.