<meta charset="utf-8">

<title>CSS Values and Units Test: support for the ex unit</title>

<link rel="author" title="Cameron McCormack" href="mailto:cam@mcc.id.au">

<link rel="help" href="https://drafts.csswg.org/css-values-3/#font-relative-lengths">

<link rel="match" href="reference/ex-unit-002-ref.html">

<meta name="assert" content="Even in vertical writing modes, the ex unit equals the x-height of the first available font if it has reliable metrics for the x-height.">

@font-face {

font-family: ExTest;

src: url(resources/ExTest.woff);

div {

height: 10px;

background-color: blue;

margin-top: 10px;

.test {

writing-mode: vertical-rl;

width: 10ex;

.ref {

width: 100px;

<p>The test passes if there are two blue rectangles of equal length.</p>

<div class="test" style="font: 80px ExTest;"></div>

<div class="ref"></div>