How to detect page zoom level in all modern browsers?

Question

1. How can I detect the page zoom level in all modern browsers? While this thread tells how to do it in IE7 and IE8, I can\'t find a good cross-browser solution.

Answer 1

My coworker and I used the script from https://github.com/tombigel/detect-zoom. In addition, we also dynamically created a svg element and check its currentScale property. It works great on Chrome and likely most browsers too. On FF the "zoom text only" feature has to be turned off though. SVG is supported on most browsers. At the time of this writing, tested on IE10, FF19 and Chrome28.

var svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
svg.setAttribute('xmlns', 'http://www.w3.org/2000/svg');
svg.setAttribute('version', '1.1');
document.body.appendChild(svg);
var z = svg.currentScale;
... more code ...
document.body.removeChild(svg);