How to remove extra space below the image inside div?

By default, an image is rendered inline, like a letter so it sits on the same line that a, b, c and d sit on.

There is space below that line for the descenders you find on letters like g, j, p and q.

Demonstration of descenders

You can:

  • adjust the vertical-align of the image to position it elsewhere (e.g. the middle) or
  • change the display so it isn't inline.
div {
  border: solid black 1px;
  margin-bottom: 10px;
}

#align-middle img {
  vertical-align: middle;
}

#align-base img {
  vertical-align: bottom;
}

#display img {
  display: block;
}
<div id="default">
<h1>Default</h1>
  The quick brown fox jumps over the lazy dog <img src="https://upload.wikimedia.org/wikipedia/commons/thumb/f/f2/VangoghStarry-night2.jpg/300px-VangoghStarry-night2.jpg" alt="">
</div>

<div id="align-middle">
<h1>vertical-align: middle</h1>
  The quick brown fox jumps over the lazy dog <img src="https://upload.wikimedia.org/wikipedia/commons/thumb/f/f2/VangoghStarry-night2.jpg/300px-VangoghStarry-night2.jpg" alt=""> </div>

  <div id="align-base">
<h1>vertical-align: bottom</h1>
  The quick brown fox jumps over the lazy dog <img src="https://upload.wikimedia.org/wikipedia/commons/thumb/f/f2/VangoghStarry-night2.jpg/300px-VangoghStarry-night2.jpg" alt=""> </div>

<div id="display">
<h1>display: block</h1>
  The quick brown fox jumps over the lazy dog <img src="https://upload.wikimedia.org/wikipedia/commons/thumb/f/f2/VangoghStarry-night2.jpg/300px-VangoghStarry-night2.jpg" alt="">
</div>

Quick fix:

To remove the gap under the image, you can:

  • Set the vertical-align property of the image to vertical-align: bottom; vertical-align: top; or vertical-align: middle;
  • Set the display property of the image to display:block;

See the following code for a live demo:

See the following code for a live demo:

#vAlign img {
  vertical-align :bottom;
}
#block img{
  display:block;
}

div {border: 1px solid red;width:100px;}
img {width:100px;}
<p>No fix:</p>
<div><img src="http://i.imgur.com/RECDV24.jpg" /></div>

<p>With vertical-align:bottom; on image:</p>
<div id="vAlign"><img src="http://i.imgur.com/RECDV24.jpg" /></div>

<p>With display:block; on image:</p>
<div id="block"><img src="http://i.imgur.com/RECDV24.jpg" /></div>

Explanation: why is there a gap under the image?

The gap or extra space under the image isn't a bug or issue, it is the default behaviour. The root cause is that images are replaced elements (_see MDN replaced elements_). This allows them to "act like image" and have their own intrinsic dimensions, aspect ratio....
Browsers compute their display property to inline but they give them a special behaviour which makes them closer to inline-block elements (as you can vertical align them, give them a height, top/bottom margin and padding, transforms ...).

This also means that:

<img> has no baseline, so when images are used in an inline formatting context with vertical-align: baseline, the bottom of the image will be placed on the text baseline.
(_source: MDN, emphasis mine_)

As browsers by default compute the vertical-align property to baseline, this is the default behaviour. The following image shows where the baseline is located on text:

Location of the baseline on text (Image source)

Baseline aligned elements need to keep space for the descenders that extend below the baseline (like j, p, g ...) as you can see in the above image. In this configuration, the bottom of the image is aligned on the baseline as you can see in this example:

div{border:1px solid red;font-size:30px;}
img{width:100px;height:auto;}
<div>
  <img src="http://i.imgur.com/RECDV24.jpg" />jpq are letters with descender
</div>

This is why the default behaviour of the <img> tag creates a gap at the bottom of it's container and why changing the vertical-align property or the display property removes it as in the following demo:

div {width: 100px;border: 1px solid red;}
img {width: 100px;height: auto;}

.block img{
  display:block;
}
.bottom img{
  vertical-align:bottom;
}
<p>Default:</p>
<div>
  <img src="http://i.imgur.com/RECDV24.jpg" />
</div>
<p>With display:block;</p>
<div class="block">
  <img src="http://i.imgur.com/RECDV24.jpg" />
</div>
<p>With vertical-align:bottom;</p>
<div class="bottom">
  <img src="http://i.imgur.com/RECDV24.jpg" />
</div>

The included image is public domain and sourced from Wikimedia Commons