justify-content

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

/* Positional alignment */
justify-content: center;     /* Pack items around the center */
justify-content: start;      /* Pack items from the start */
justify-content: end;        /* Pack items from the end */
justify-content: flex-start; /* Pack flex items from the start */
justify-content: flex-end;   /* Pack flex items from the end */
justify-content: left;       /* Pack items from the left */
justify-content: right;      /* Pack items from the right */
/* Baseline alignment */
justify-content: baseline;
justify-content: first baseline;
justify-content: last baseline;
/* Distributed alignment */
justify-content: space-between; /* Distribute items evenly
                                   The first item is flush with the start,
                                   the last is flush with the end */
justify-content: space-around;  /* Distribute items evenly
                                   Items have a half-size space
                                   on either end */
justify-content: space-evenly;  /* Distribute items evenly
                                   Items have equal space around them */
justify-content: stretch;       /* Distribute items evenly
                                   Stretch 'auto'-sized items to fit
                                   the container */
/* Overflow alignment */
justify-content: safe center;
justify-content: unsafe center;
/* Global values */
justify-content: inherit;
justify-content: initial;
justify-content: unset;

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

Syntax

Values

start

The items are packed flush to each other toward the start edge of the alignment container in the main axis.

end

The items are packed flush to each other toward the end edge of the alignment container in the main axis.

flex-start

The items are packed flush to each other toward the edge of the alignment container depending on the flex container's main-start side.
This only applies to flex layout items. For items that are not children of a flex container, this value is treated like start.

flex-end

The items are packed flush to each other toward the edge of the alignment container depending on the flex container's main-end side.
This only applies to flex layout items. For items that are not children of a flex container, this value is treated like end.

center

The items are packed flush to each other toward the center of the of the alignment container along the main axis.

left

The items are packed flush to each other toward the left edge of the alignment container. If the property’s axis is not parallel with the inline axis, this value behaves like start.

right

The items are packed flush to each other toward the right edge of the alignment container in the appropriate axis. If the property’s axis is not parallel with the inline axis, this value behaves like start.

baseline
first baseline
last baseline

Specifies participation in first- or last-baseline alignment: aligns the alignment baseline of the box’s first or last baseline set with the corresponding baseline in the shared first or last baseline set of all the boxes in its baseline-sharing group.
The fallback alignment for first baseline is start, the one for last baseline is end.

space-between

The items are evenly distributed within the alignment container along the main axis. The spacing between each pair of adjacent items is the same. The first item is flush with the main-start edge, and the last item is flush with the main-end edge.

space-around

The items are evenly distributed within the alignment container along the main axis. The spacing between each pair of adjacent items is the same. The empty space before the first and after the last item equals half of the space between each pair of adjacent items.

space-evenly

The items are evenly distributed within the alignment container along the main axis. The spacing between each pair of adjacent items, the main-start edge and the first item, and the main-end edge and the last item, are all exactly the same.

stretch

If the combined size of the items is less than the size of the alignment container, any auto-sized items have their size increased equally (not proportionally), while still respecting the constraints imposed by max-height/max-width (or equivalent functionality), so that the combined size exactly fills the alignment container along the main axis.

safe

If the size of the item overflows the alignment container, the item is instead aligned as if the alignment mode were start.

unsafe

Regardless of the relative sizes of the item and alignment container, the given alignment value is honored.

Formal syntax

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

Example

CSS content

#container {
  display: flex;
  justify-content: space-between; /* Can be changed in the live sample */
}
#container > div {
  width: 100px;
  height: 100px;
  background: linear-gradient(-45deg, #788cff, #b4c8ff);
}

<div id="container">
  <div></div>
  <div></div>
  <div></div>
</div>
<select id="justifyContent">
  <option value="start">start</option>
  <option value="end">end</option>
  <option value="flex-start">flex-start</option>
  <option value="flex-end">flex-end</option>
  <option value="center">center</option>
  <option value="left">left</option>
  <option value="right">right</option>
  <option value="baseline">baseline</option>
  <option value="first baseline">first baseline</option>
  <option value="last baseline">last baseline</option>
  <option value="space-between" selected>space-between</option>
  <option value="space-around">space-around</option>
  <option value="space-evenly">space-evenly</option>
  <option value="stretch">stretch</option>
</select>

var justifyContent = document.getElementById("justifyContent");
justifyContent.addEventListener("change", function (evt) {
  document.getElementById("container").style.justifyContent =
      evt.target.value;
});

Result

Specifications

Browser compatibility

[1] Firefox supports only single-line flexbox until Firefox 27. To activate flexbox support, for Firefox 18 and 19, the user has to change the about:config preference layout.css.flexbox.enabled to true.

[2] In addition to the unprefixed support, Gecko 48.0 (Firefox 48.0 / Thunderbird 48.0 / SeaMonkey 2.45) added support for a -webkit prefixed version of the property for web compatibility reasons behind the preference layout.css.prefixes.webkit, defaulting to false. Since Gecko 49.0 (Firefox 49.0 / Thunderbird 49.0 / SeaMonkey 2.46) the preference defaults to true.

[3] Older versions of the specification treat absolutely positioned children as though they are a 0 by 0 flex items. Later versions of the specification take them out of the flow and set their positions based on align and justify properties. Chrome implements the new behavior beginning with Chrome 52.

[4] The keywords start, end, left, and right are recognized but are not implemented.

[5] Versions prior to Gecko 52 (Firefox 52.0 / Thunderbird 52.0 / SeaMonkey 2.49) already recognize the left and right keywords, but don't implement them.

See also

• Using CSS flexible boxes