title: Iframe get visible size
body: <p>Inside the iframe I need to figure out what exactly is the visual size(using js or jquery).</p>
  
  <p>In this example, only the part of an iframe is shown.
  Iframe size is 300x300 but the div will limit it to 300x100.</p>
  
  <pre><code>&lt;div style="max-width: 300px; max-height: 100px; overflow: hidden"&gt;
  &lt;iframe width="300" height="300" src="http://www.rapidtables.com/web/tools/window-size.htm" style="border:none"&gt;&lt;/iframe&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>How can i detect that actual visible dimensions from inside the iframe?</p>
  
  <p>Tried</p>
  
  <pre><code>window.clientHeight
  window.outerHeight
  window.innerHeight
  window.availableHeight
  $(window).height();
  </code></pre>