manifest lang / dir browser support

Published 2026-09-04Updated 2026-09-14By Carey Gill · Editorial process

The Web App Manifest’s dir and lang members set a default text direction and language for the manifest’s localizable members — name, short_name, and icons.

Browser support

MDN’s manifest reference notes that, as implemented today, dir, lang, and iarc_rating_id are not implemented by browsers. There is no per-browser support table to cite for these two members, because no browser currently acts on them.

How to use it

You can still declare dir and lang in your manifest — they are valid, optional members per the spec:

{
  "name": "SuperSausage",
  "dir": "rtl",
  "lang": "ar",
  "start_url": "."
}

How to detect it at runtime

Per MDN, dir, lang, and iarc_rating_id are not implemented by browsers.

function applyDocumentLocale(lang, dir) {
  // The manifest's `dir`/`lang` members are not implemented by browsers.
  if (typeof document === 'undefined') {
    return;
  }
  document.documentElement.lang = lang;
  document.documentElement.dir = dir;
}

Practical checklist

Do not rely on the manifest’s dir or lang members for direction or language control — MDN states neither is implemented by any browser.
The manifest’s dir/lang members are separate from a document’s own <html dir>/<html lang> attributes; declaring one does not set the other.
Declaring dir/lang in the manifest is still spec-valid, even though MDN states neither is implemented by any browser today.

Where to go next

← Back to the Compatibility explorer.