helpers : isFrozenUA()

isFrozenUA(ua: string): boolean

Determines whether a given User-Agent string matches Chrome’s reduced (frozen) User-Agent pattern:

Mozilla/5.0 ([unifiedPlatform]) AppleWebKit/537.36 (KHTML, like Gecko)
Chrome/[majorVersion].0.0.0 [deviceCompat] Safari/537.36

Token	Possible values
[unifiedPlatform]	Desktop: Windows NT 10.0; Win64; x64 Macintosh; Intel Mac OS X 10_15_7 X11; Linux x86_64 X11; CrOS x86_64 14541.0.0 Fuchsia Mobile: Linux; Android 10; K
[deviceCompat]	Desktop/Tablet: '' (empty) Mobile: Mobile

TIP

Learn how to identify the real device behind a reduced user-agent here

Code Example

example-freeze-test.js

import { isFrozenUA } from 'ua-parser-js/helpers';

const regularMobileUA = "Mozilla/5.0 (Linux; Android 9; SM-A205U) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.1234.56 Mobile Safari/537.36";
const frozenMobileUA = "Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.0.0 Mobile Safari/537.36";

console.log(isFrozenUA(regularMobileUA));
// false

console.log(isFrozenUA(frozenMobileUA));
// true

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References

• User-Agent Reduction🡥 —The Chromium Projects