Can I use
?

asm.js

- OTHER

An extraordinarily optimizable, low-level subset of JavaScript, intended to be a compile target from languages like C++.

Chrome

  1. ❌ 4 - 27: Not supported
  2. ◐ 28 - 134: Partial support
  3. ◐ 135: Partial support
  4. ◐ 136 - 138: Partial support

Edge

  1. ❌ 12: Disabled by default
  2. ✅ 13 - 18: Supported
  3. ◐ 79 - 134: Partial support
  4. ◐ 135: Partial support

Safari

  1. ❌ 3.1 - 18.3: Not supported
  2. ❌ 18.4: Not supported
  3. ❌ 18.5 - TP: Not supported

Firefox

  1. ❌ 2 - 21: Not supported
  2. ✅ 22 - 136: Supported
  3. ✅ 137: Supported
  4. ✅ 138 - 140: Supported

Opera

  1. ❌ 9 - 12.1: Not supported
  2. ◐ 15 - 116: Partial support
  3. ◐ 117: Partial support

IE

  1. ❌ 5.5 - 10: Not supported
  2. ❌ 11: Not supported

Chrome for Android

  1. ◐ 135: Partial support

Safari on iOS

  1. ❌ 3.2 - 18.3: Not supported
  2. ❌ 18.4: Not supported
  3. ❌ 18.5: Not supported

Samsung Internet

  1. ❌ 4: Not supported
  2. ◐ 5 - 26: Partial support
  3. ◐ 27: Partial support

Opera Mini

  1. ❌ all: Not supported

Opera Mobile

  1. ❌ 10 - 12.1: Not supported
  2. ◐ 80: Partial support

UC Browser for Android

  1. ◐ 15.5: Partial support

Android Browser

  1. ❌ 2.1 - 4.4.4: Not supported
  2. ◐ 135: Partial support

Firefox for Android

  1. ✅ 137: Supported

QQ Browser

  1. ◐ 14.9: Partial support

Baidu Browser

  1. ◐ 13.52: Partial support

KaiOS Browser

  1. ✅ 2.5: Supported
  2. ✅ 3: Supported

asm.js is mostly rendered obsolete with the introduction of WebAssembly and is therefore no longer recommended

Resources:
Homepage
Bringing Asm.js to Chakra and Microsoft Edge
Microsoft Edge support announcement
MDN article about asm.js
Wikipedia article about asm.js
Source for spec and tools