How to remove the space between inline-block elements?

Since this answer has become rather popular, I'm rewriting it significantly.

Let's not forget the actual question that was asked:

How to remove the space between inline-block elements? I was hoping for a CSS solution that doesn't require the HTML source code to be tampered with. Can this issue be solved with CSS alone?

It is possible to solve this problem with CSS alone, but there are no completely robust CSS fixes.

The solution I had in my initial answer was to add font-size: 0 to the parent element, and then declare a sensible font-size on the children.

http://jsfiddle.net/thirtydot/dGHFV/1361/

This works in recent versions of all modern browsers. It works in IE8. It does not work in Safari 5, but it does work in Safari 6. Safari 5 is nearly a dead browser (0.33%, August 2015).

Most of the possible issues with relative font sizes are not complicated to fix.

However, while this is a reasonable solution if you specifically need a CSS only fix, it's not what I recommend if you're free to change your HTML (as most of us are).

This is what I, as a reasonably experienced web developer, actually do to solve this problem:

<p>
    <span>Foo</span><span>Bar</span>
</p>

Yes, that's right. I remove the whitespace in the HTML between the inline-block elements.

It's easy. It's simple. It works everywhere. It's the pragmatic solution.

You do sometimes have to carefully consider where whitespace will come from. Will appending another element with jQuery add whitespace? No, not if you do it properly.

Let's go on a magical journey of different ways to remove the whitespace, with some new HTML:

<ul>
    <li>Item 1</li>
    <li>Item 2</li>
    <li>Item 3</li>
</ul>

• You can do this, as I usually do:

  <ul>
      <li>Item 1</li><li>Item 2</li><li>Item 3</li>
  </ul>

  http://jsfiddle.net/thirtydot/dGHFV/1362/

• Or, this:

  <ul>
      <li>Item 1</li
      ><li>Item 2</li
      ><li>Item 3</li>
  </ul>

• Or, use comments:

  <ul>
      <li>Item 1</li><!--
      --><li>Item 2</li><!--
      --><li>Item 3</li>
  </ul>

• Or, you can even skip certain closing tags entirely (all browsers are fine with this):

  <ul>
      <li>Item 1
      <li>Item 2
      <li>Item 3
  </ul>

Now that I've gone and bored you to death with "one thousand different ways to remove whitespace, by thirtydot", hopefully you've forgotten all about font-size: 0.

Ok, although I've upvoted both the font-size: 0; and the not implemented CSS3 feature answers, after trying I found out that none of them is a real solution.

Actually, there is not even one workaround without strong side effects.

Then I decided to remove the spaces (this answers is about this argument) between the inline-block divs from my HTML source (JSP), turning this:

<div class="inlineBlock">
    I'm an inline-block div
</div>
<div class="inlineBlock">
    I'm an inline-block div
</div>

to this

<div class="inlineBlock">
    I'm an inline-block div
</div><div class="inlineBlock">
    I'm an inline-block div
</div>

that is ugly, but working.

But, wait a minute... what if I'm generating my divs inside Taglibs loops (Struts2, JSTL, etc...) ?

For example:

<s:iterator begin="0" end="6" status="ctrDay">
    <br/>
    <s:iterator begin="0" end="23" status="ctrHour">
        <s:push value="%{days[#ctrDay.index].hours[#ctrHour.index]}">
            <div class="inlineBlock>
                I'm an inline-block div in a matrix 
                (Do something here with the pushed object...)
           </div>
       </s:push>
    </s:iterator>
</s:iterator>

It is absolutely not thinkable to inline all that stuff, it would mean

<s:iterator begin="0" end="6" status="ctrDay">
    <br/>
    <s:iterator begin="0" end="23" status="ctrHour"><s:push value="%{days[#ctrDay.index].hours[#ctrHour.index]}"><div class="inlineBlock>
                I'm an inline-block div in a matrix             
                (Do something here with the pushed object...)
           </div></s:push></s:iterator>
</s:iterator>

that is not readable, hard to mantain and understand, etc...

The solution i found:

use HTML comments to connect the end of one div to the begin of the next one!

<s:iterator begin="0" end="6" status="ctrDay">
   <br/>
   <s:iterator begin="0" end="23" status="ctrHour"><!--
    --><s:push value="%{days[#ctrDay.index].hours[#ctrHour.index]}"><!--
        --><div class="inlineBlock>
                I'm an inline-block div in a matrix             
                (Do something here with the pushed object...)
           </div><!--
    --></s:push><!--
--></s:iterator>
</s:iterator>

This way you will have a readable and correctly indented code.

And, as a positive side effect, the HTML source, although infested by empty comments, will result correctly indented;

let's take the first example, imho this:

    <div class="inlineBlock">
        I'm an inline-block div
    </div><!--
 --><div class="inlineBlock">
        I'm an inline-block div
    </div>

is better than this

    <div class="inlineBlock">
         I'm an inline-block div
    </div><div class="inlineBlock">
         I'm an inline-block div
    </div>

Hope that helps...