 <p>Zoom is not included in the CSS specification, but it is supported in IE, Safari 4, Chrome (and you can get a somewhat similar effect in Firefox with <code>-moz-transform: scale(x)</code> since 3.5). See <a href="http://www.fix-css.com/2011/05/css-zoom/">here</a>.</p> <p>So, all browsers</p> <pre><code> zoom: 2; zoom: 200%; </code></pre> <p>will zoom your object in by 2, so it's like doubling the size. Which means if you have </p> <pre><code>a:hover { zoom: 2; } </code></pre> <p>On hover, the <code>&lt;a&gt;</code> tag will zoom by 200%.</p> <p>Like I say, in FireFox 3.5+ use <code>-moz-transform: scale(x)</code>, it does much the same thing.</p> <p>Edit: In response to the comment from <code>thirtydot</code>, I will say that <code>scale()</code> is not a complete replacement. It does not expand in line like <code>zoom</code> does, rather it will expand out of the box and over content, not forcing other content out of the way. See this in action <a href="http://www.w3schools.com/cssref/playit.asp?filename=playcss_transform_scale">here</a>. Furthermore, it seems that <code>zoom</code> is not supported in Opera.</p> <p><a href="http://htmlcssjavascript.com/css/using-css-zoom-and-css-transforms-for-a-better-increase-text-size-button/">This</a> post gives a useful insight into ways to work around incompatibilities with <code>scale</code> and workarounds for it using jQuery.</p>