Spellcheck attribute

- LS

Attribute for input/textarea fields to enable/disable the browser's spellchecker.

IE

  1. 5.5 - 9: Not supported
  2. 10: Supported
  3. 11: Supported

Edge

  1. 12 - 79: Supported
  2. 80: Supported

Firefox

  1. 2 - 73: Supported
  2. 74: Supported
  3. 75 - 76: Supported

Chrome

  1. 4 - 8: Not supported
  2. 9 - 79: Supported
  3. 80: Supported
  4. 81 - 83: Supported

Safari

  1. 3.1 - 5: Not supported
  2. 5.1 - 12.1: Supported
  3. 13: Supported
  4. 13.1 - TP: Supported

Opera

  1. 9 - 10.1: Not supported
  2. 10.5 - 65: Supported
  3. 66: Supported

iOS Safari

  1. 3.2 - 13.2: Partial support
  2. 13.3: Partial support
  3. 13.4: Partial support

Opera Mini

  1. all: Partial support

Android Browser

  1. 2.1 - 4.4.4: Partial support
  2. 80: Partial support

Blackberry Browser

  1. 7: Partial support
  2. 10: Supported

Opera Mobile

  1. 10 - 12.1: Partial support
  2. 46: Partial support

Chrome for Android

  1. 80: Partial support

Firefox for Android

  1. 68: Partial support

IE Mobile

  1. 10: Partial support
  2. 11: Partial support

UC Browser for Android

  1. 12.12: Partial support

Samsung Internet

  1. 4 - 10.1: Partial support
  2. 11.1: Partial support

QQ Browser

  1. 1.2: Supported

Baidu Browser

  1. 7.12: Partial support

KaiOS Browser

  1. 2.5: Not supported

The partial support in mobile browsers results from their OS generally having built-in spell checking instead of using the wavy underline to indicate misspelled words. spellcheck="false" does not seem to have any effect in these browsers.

Browsers have different behavior in how they deal with spellchecking in combination with the the lang attribute. Generally spelling is based on the browser's language, not the language of the document.

Resources:
MDN Web Docs - Controlling spell checking