<!doctype html>
<html>
  <head>
    <title>mathsize</title>
    <meta charset="utf-8"/>
  </head>
  <body>

    <!-- The style attribute should have the same effect as the mathsize
         attribute. Note that the exact size for "small" and "big" is not
         specified by the MathML specification. 0.75em and 2em are the values
         used by WebKit. --> 
    <div>
      <math>
        <mi style="font-size: 0.75em;">x</mi>
        <mi style="font-size: 1em;">x</mi>
        <mi style="font-size: 1.5em;">x</mi>
        <mi style="font-size: 2em;">x</mi>
      </math>
    </div>

  </body>
</html>