Web app manifests

Web app manifests are part of a collection of web technologies called progressive web apps (PWAs), which are websites that can be installed to a device's homescreen without an app store. Unlike regular web apps with simple homescreen links or bookmarks, PWAs can be downloaded in advance and can work offline, as well as use regular Web APIs.

The web app manifest provides information about a web application in a JSON text file, necessary for the web app to be downloaded and be presented to the user similarly to a native app (e.g., be installed on the homescreen of a device, providing users with quicker access and a richer experience). PWA manifests include its name, author, icon(s), version, description, and list of all the necessary resources (among other things).

Members

Web manifests can contain the following keys. Click on each one to link through to more information about it:

Example manifest

{
  "$schema": "https://json.schemastore.org/web-manifest-combined.json",
  "name": "HackerWeb",
  "short_name": "HackerWeb",
  "start_url": ".",
  "display": "standalone",
  "background_color": "#fff",
  "description": "A readable Hacker News app.",
  "icons": [{
    "src": "images/touch/homescreen48.png",
    "sizes": "48x48",
    "type": "image/png"
  }, {
    "src": "images/touch/homescreen72.png",
    "sizes": "72x72",
    "type": "image/png"
  }, {
    "src": "images/touch/homescreen96.png",
    "sizes": "96x96",
    "type": "image/png"
  }, {
    "src": "images/touch/homescreen144.png",
    "sizes": "144x144",
    "type": "image/png"
  }, {
    "src": "images/touch/homescreen168.png",
    "sizes": "168x168",
    "type": "image/png"
  }, {
    "src": "images/touch/homescreen192.png",
    "sizes": "192x192",
    "type": "image/png"
  }],
  "related_applications": [{
    "platform": "play",
    "url": "https://play.google.com/store/apps/details?id=cheeaun.hackerweb"
  }]
}

Deploying a manifest

Web app manifests are deployed in your HTML pages using a <link> element in the <head> of a document:

<link rel="manifest" href="manifest.json">

The .webmanifest extension is specified in the Media type registration section of the specification (the response of the manifest file should return Content-Type: application/manifest+json). Browsers generally support manifests with other appropriate extensions like .json (Content-Type: application/json).

If the manifest requires credentials to fetch, the crossorigin attribute must be set to use-credentials, even if the manifest file is in the same origin as the current page.

<link rel="manifest" href="/app.webmanifest" crossorigin="use-credentials">

Splash screens

In some browsers (Chrome 47 and later, for example), a splash screen is displayed for sites launched from a homescreen. This splash screen is auto-generated from properties in the web app manifest, specifically:

Specifications

Specification
Web App Manifest

Browser compatibility

BCD tables only load in the browser

See also