Vertical align an absolute div

Question

I have a div, it's has no declared height and is positioned absolute.

How can I vertically align it?

<div class="valign"><a href="#"><img src="whatever.jpg"></a></div>

.valign{
    position: absolute;
    left: 10px;
}

No flex box please.

Answer 1

.valign {
  position: absolute;
  top: 50%;
  left: 10px;
  -webkit-transform: translateY(-50%);
  -moz-transform: translateY(-50%);
  -ms-transform: translateY(-50%);
  transform: translateY(-50%);
}