Summary

The CSS justify-content property defines how the browser distributes space between and around flex items along the main-axis of their container.

The alignment is done after the lengths and auto margins are applied, meaning that, if there is at least one flexible element, with flex-grow different than 0, it will have no effect as there won't be any available space.

Do not assume that this property will only apply on flex containers in the future and therefore do not simply hide it by setting another display value. The CSSWG is working into extending its usage to any block element. The draft specification is still in its very early stage and isn't implement yet.

See Using CSS flexible boxes for more properties and information.

Syntax

/* Pack flex items from the start */
justify-content: flex-start;

/* Pack items from the end */
justify-content: flex-end;

/* Pack items around the center */ 
justify-content: center;

/* Distribute items evenly
The first item at the start, the last at the end */
justify-content: space-between;

/* Distribute items evenly
Items have equal space around them */
justify-content: space-around;

/* Global values */
justify-content: inherit;
justify-content: initial;
justify-content: unset;

Values

flex-start
The flex items are packed starting from the main-start. Margins of the first flex item is flushed with the main-start edge of the line and each following flex item is flushed with the preceding.
flex-end
The flex items are packed starting from the main-end. The margin edge of the last flex item is flushed with the main-end edge of the line and each preceding flex item is flushed with the following.
center
The flex items are packed toward the center of the line. The flex items are flushed with each other and aligned in the center of the line. Space between the main-start edge of the line and first item and between main-end and the last item of the line is the same.
space-between
Flex items are evenly distributed along the line. The spacing is done such as the space between two adjacent items is the same. Main-start edge and main-end edge are flushed with respectively first and last flex item edges.
space-around
Flex items are evenly distributed so that the space between two adjacent items is the same. The empty space before the first and after the last items equals half of the space between two adjacent items.

Formal syntax

flex-start | flex-end | center | space-between | space-around

Examples

HTML Content

<div id="container">
  <p>justify-content: flex-start</p>
  <div id="flex-start">
    <div></div>
    <div></div>
    <div></div>
  </div>

  <p>justify-content: flex-end</p>
  <div id="flex-end">
    <div></div>
    <div></div>
    <div></div>
  </div>

  <p>justify-content: center</p>
  <div id="center">
    <div></div>
    <div></div>
    <div></div>
  </div>

  <p>justify-content: space-between</p>
  <div id="space-between">
    <div></div>
    <div></div>
    <div></div>
  </div>

  <p>justify-content: space-around</p>
  <div id="space-around">
    <div></div>
    <div></div>
    <div></div>
  </div>
</div>

CSS

#container > div {
  display: flex;
  font-family: "Courier New", "Lucida Console", monospace;
}

#container > div > div {
  width: 50px;
  height: 50px;
  background: linear-gradient(-45deg, #788cff, #b4c8ff);
}

#flex-start {
  justify-content: flex-start;
}

#center {
  justify-content: center;
}

#flex-end {
  justify-content: flex-end;
}

#space-between {
  justify-content: space-between;
}

#space-around {
  justify-content: space-around;
}

Results in:

Specifications

Specification Status Comment
CSS Flexible Box Layout Module
The definition of 'justify-content' in that specification.
Last Call Working Draft Initial definition

Browser compatibility

Feature Firefox (Gecko) Chrome Internet Explorer Opera Safari
Basic support 18.0 (18.0) (behind a pref) [1]
20.0 (20.0)
21.0-webkit 11 12.10 Not supported
Feature Firefox Mobile (Gecko) Android IE Phone Opera Mobile Safari Mobile
Basic support ? ? Not supported 12.10 Not supported

[1] Firefox supports only single-line flexbox until Firefox 28. To activate flexbox support, for Firefox 18 and 19, the user has to change the about:config preference "layout.css.flexbox.enabled" to true.

See also

Document Tags and Contributors

Last updated by: fscholz,