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rem (root em) units

- CR

Type of unit similar to em, but relative only to the root element, not any parent element. Thus compounding does not occur as it does with em units.

Chrome

  1. ✅ 4 - 134: Supported
  2. ✅ 135: Supported
  3. ✅ 136 - 138: Supported

Edge

  1. ✅ 12 - 134: Supported
  2. ✅ 135: Supported

Safari

  1. ❌ 3.1 - 4: Not supported
  2. ✅ 5 - 18.3: Supported
  3. ✅ 18.4: Supported
  4. ✅ 18.5 - TP: Supported

Firefox

  1. ❌ 2 - 3.5: Not supported
  2. ✅ 3.6 - 136: Supported
  3. ✅ 137: Supported
  4. ✅ 138 - 140: Supported

Opera

  1. ❌ 9 - 11.5: Not supported
  2. ✅ 11.6 - 116: Supported
  3. ✅ 117: Supported

IE

  1. ❌ 5.5 - 8: Not supported
  2. ◐ 9 - 10: Partial support
  3. ✅ 11: Supported

Chrome for Android

  1. ✅ 135: Supported

Safari on iOS

  1. ❌ 3.2: Not supported
  2. ✅ 4 - 4.3: Supported
  3. ◐ 5: Partial support
  4. ✅ 6 - 18.3: Supported
  5. ✅ 18.4: Supported
  6. ✅ 18.5: Supported

Samsung Internet

  1. ✅ 4 - 26: Supported
  2. ✅ 27: Supported

Opera Mini

  1. ✅ all: Supported

Opera Mobile

  1. ❌ 10 - 11.5: Not supported
  2. ✅ 12 - 12.1: Supported
  3. ✅ 80: Supported

UC Browser for Android

  1. ✅ 15.5: Supported

Android Browser

  1. ✅ 2.1 - 4.4.4: Supported
  2. ✅ 135: Supported

Firefox for Android

  1. ✅ 137: Supported

QQ Browser

  1. ✅ 14.9: Supported

Baidu Browser

  1. ✅ 13.52: Supported

KaiOS Browser

  1. ✅ 2.5: Supported
  2. ✅ 3: Supported
Resources:
REM Polyfill
Article on usage