 <p>You probably need to reconvert this via a tool that fixes vertical metrics for Mac/PC. (eg. <a href="https://stackoverflow.com/questions/10044130/custom-fonts-with-differrent-vertical-metrics-between-oss">Fontsquirrel</a>)</p> <p>As this happens across browsers this seems like the problem described in this thread: <a href="https://stackoverflow.com/questions/2854028/mac-vs-windows-browser-font-height-rendering-issue">Mac vs. Windows Browser Font Height Rendering Issue</a>. </p> <p>Another option via the commandline seems to be fiddling with the TTX configuration via <a href="https://github.com/behdad/fonttools/" rel="nofollow">FontTools</a></p>