Div height:0px does not work?

If you really want to be sure it's gonna be have no height you could use something like this:

display: block;
line-height:0;
height: 0;
overflow: hidden;

If you're still having problems on IE, you could also add

zoom: 1;

to it in a stylesheet targeted at IE with a conditional comment. That'll trigger the hasLayout property in IE.

And display:none isn't the same as setting it to zero height. Just look at the various clearfix solutions for a case where not removing it from the flow is crucial.

Set overflow:hidden. Otherwise the content will expand the wrapping element.

Try to also set line-height: 0;

And if you want to hide your div completely, use display: none;

For me, on Windows 10, Firefox 58.0.1, it wouldn't hide completely unless using this:

display: block !important;
line-height: 0 !important;
height: 0 !important;
overflow: hidden !important;
zoom: 1 !important;
padding: 0 !important;
margin-bottom: 0;
border: none;

Try overflow:hidden

You could try adding "overflow:hidden" to the style

Not quite sure what you're trying to do, out of context, but try this:

display:none;
overflow:hidden:
height:0;
line-height:0;
border:0;
margin:0;

You haven't said which browser you're using, but I'm assuming IE, as it's the only browser I know of which mistakes height for min-height . Like everyone else has already said, overflow:hidden; will work, or line-height: 0;, but you only need one of them.

Setting height: 0; will have allready triggered IEs hasLayout, so no need for zoom:1; in this case.

The other answers cover this well. Just want to add that if you have tried everything else and the <div> still is visible, then there may be a min-height: that is the culprit.