JavaScript Feature Detection Method


Example

This method looks for the existence of browser specific things. This would be more difficult to spoof, but is not guaranteed to be future proof.

// Opera 8.0+
var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;

// Firefox 1.0+
var isFirefox = typeof InstallTrigger !== 'undefined';
    
// At least Safari 3+: "[object HTMLElementConstructor]"
var isSafari = Object.prototype.toString.call(window.HTMLElement).indexOf('Constructor') > 0;

// Internet Explorer 6-11
var isIE = /*@cc_on!@*/false || !!document.documentMode;

// Edge 20+
var isEdge = !isIE && !!window.StyleMedia;

// Chrome 1+
var isChrome = !!window.chrome && !!window.chrome.webstore;

// Blink engine detection
var isBlink = (isChrome || isOpera) && !!window.CSS;

Successfully tested in:

  • Firefox 0.8 - 44
  • Chrome 1.0 - 48
  • Opera 8.0 - 34
  • Safari 3.0 - 9.0.3
  • IE 6 - 11
  • Edge - 20-25

Credit to Rob W