html - JavaScript: Get image dimensions

Question

I only have a URL to an image. I need to determine the height and width of this image using only JavaScript. The image cannot be visible to the user on the page. How can I get its dimensions?

Answer 1

var img = new Image();

img.onload = function(){
  var height = img.height;
  var width = img.width;

  // code here to use the dimensions
}

img.src = url;