ECMAScript 5

- OTHER

Full support for the ECMAScript 5 specification. Features include Function.prototype.bind, Array methods like indexOf, forEach, map & filter, Object methods like defineProperty, create & keys, the trim method on Strings and many more.

Chrome

  1. 4 - 18: Partial support
  2. 19 - 22: Partial support
  3. 23 - 121: Supported
  4. 122: Supported
  5. 123 - 125: Supported

Edge

  1. 12 - 120: Supported
  2. 121: Supported

Safari

  1. 3.1 - 5.1: Partial support
  2. 6 - 17.2: Supported
  3. 17.3: Supported
  4. 17.4 - TP: Supported

Firefox

  1. 2 - 3.6: Partial support
  2. 4 - 20: Partial support
  3. 21 - 122: Supported
  4. 123: Supported
  5. 124 - 126: Supported

Opera

  1. 9 - 12: Partial support
  2. 12.1: Partial support
  3. 15 - 105: Supported
  4. 106: Supported

IE

  1. 5.5 - 7: Not supported
  2. 8: Not supported
  3. 9: Partial support
  4. 10: Supported
  5. 11: Supported

Chrome for Android

  1. 121: Supported

Safari on iOS

  1. 3.2 - 5.1: Partial support
  2. 6 - 17.2: Supported
  3. 17.3: Supported
  4. 17.4: Supported

Samsung Internet

  1. 4 - 22: Supported
  2. 23: Supported

Opera Mini

  1. all: Partial support

Opera Mobile

  1. 10 - 12: Partial support
  2. 12.1: Partial support
  3. 73: Supported

UC Browser for Android

  1. 15.5: Supported

Android Browser

  1. 2.1 - 3: Partial support
  2. 4: Partial support
  3. 4.1 - 4.3: Partial support
  4. 4.4 - 4.4.4: Supported
  5. 121: Supported

Firefox for Android

  1. 122: Supported

QQ Browser

  1. 13.1: Supported

Baidu Browser

  1. 13.18: Supported

KaiOS Browser

  1. 2.5: Supported
  2. 3: Supported

As the specification includes many JavaScript features, un-numbered partial support varies widely and is shown in detail on the ECMAScript 5 compatibility tables by Kangax.

Resources:
Detailed compatibility tables & tests
ES5 polyfill
Polyfill for all possible ES5 features is available in the core-js library
Overview of objects & properties
Sub-features:
ECMAScript 5 Strict Mode
JSON parsing