How can you get the CSS pixel / device pixel ratio?

Question

I want to find the ratio between CSS pixels and device pixels.

Edit: I should have realized that this is just zoom level. I\'ve added an answer to t

Answer 1

There is a much better CSS/JS solution:

/** sample media query for pixel-ratio=2" **/
@media  
(-webkit-min-device-pixel-ratio: 2), 
(min-resolution: 192dpi) { 
  .pixel-ratio-holder:before {
   content: "2";
  }
}


function jsPixelRatio(){
   return window.getComputedStyle(document.querySelector('.pixel-ratio-holder'), 'before').getPropertyValue('content').replace(/[^a-z]/g,'') * 1;
}