tl;dr
Vertical align middle works, but you will have to use table-cell
on your parent element and inline-block
on the child.
This solution is not going to work in IE6 & 7.
Yours is the safer way to go for those.
But since you tagged your question with CSS3 and HTML5 I was thinking that you don't mind using a modern solution.
The classic solution (table layout)
This was my original answer. It still works fine and is the solution with the widest support. Table-layout will impact your rendering performance so I would suggest that you use one of the more modern solutions.
Here is an example
Tested in:
- FF3.5+
- FF4+
- Safari 5+
- Chrome 11+
- IE9+
HTML
<div class="cn"><div class="inner">your content</div></div>
CSS
.cn {
display: table-cell;
width: 500px;
height: 500px;
vertical-align: middle;
text-align: center;
}
.inner {
display: inline-block;
width: 200px; height: 200px;
}
Modern solution (transform)
Since transforms are fairly well supported now there is an easier way to do it.
CSS
.cn {
position: relative;
width: 500px;
height: 500px;
}
.inner {
position: absolute;
top: 50%; left: 50%;
transform: translate(-50%,-50%);
width: 200px;
height: 200px;
}
Demo
♥ my favourite modern solution (flexbox)
I started to use flexbox more and more its also well supported now Its by far the easiest way.
CSS
.cn {
display: flex;
justify-content: center;
align-items: center;
}
Demo
More examples & possibilities:
Compare all the methods on one pages