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

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

/* 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 does not take baseline values */

/* Normal alignment */
align-content: normal;

/* 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;

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 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.
normal
The items are packed in their default position as if no justify-content value was set.
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 along the main axis 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
Used alongside an alignment keyword. If the chosen keyword means that the item overflows the alignment container causing data loss, the item is instead aligned as if the alignment mode were start.
unsafe
Used alongside an alignment keyword. Regardless of the relative sizes of the item and alignment container and whether overflow which causes data loss might happen, the given alignment value is honored.

Formal syntax

normal | <content-distribution> | <overflow-position>? [ <content-position> | left | right ]

where
<content-distribution> = space-between | space-around | space-evenly | stretch
<overflow-position> = unsafe | safe
<content-position> = center | start | end | flex-start | flex-end

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);
}

Result

Specifications

Specification Status Comment
CSS Box Alignment Module Level 3
The definition of 'justify-content' in that specification.
Working Draft Adds the [ first | last ]? baseline, self-start, self-end, start, end, left, right, unsafe | safe values.
CSS Flexible Box Layout Module
The definition of 'justify-content' in that specification.
Candidate Recommendation Initial definition
Initial valuenormal
Applies toflex containers
Inheritedno
Mediavisual
Computed valueas specified
Animation typediscrete
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Browser compatibility

Support in Flex layout

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 52
Full support 52
Partial support 29
Notes
Notes Older versions of the specification treat absolute positioned children as though they are a 0 by 0 flex item. Later specification versions take the children out of the flow and set their positions based on align and justify properties. Chrome implements the new behavior beginning with Chrome 52.
Full support 21
Prefixed
Prefixed Requires the vendor prefix: -webkit-
Edge Full support 12
Full support 12
Full support 12
Prefixed
Prefixed Requires the vendor prefix: -webkit-
Firefox Full support 20
Notes
Full support 20
Notes
Notes Before Firefox 27, Firefox supported only single-line flexbox.
No support 18 — ?
Disabled
Disabled From version 18: this feature is behind the layout.css.flexbox.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
Full support 49
Prefixed
Prefixed Requires the vendor prefix: -webkit-
Full support 48
Prefixed Disabled
Prefixed Requires the vendor prefix: -webkit-
Disabled From version 48: this feature is behind the layout.css.prefixes.webkit preference (needs to be set to true). To change preferences in Firefox, visit about:config.
IE Full support 11Opera Full support 12.1Safari Full support 9WebView Android Full support 52
Full support 52
Partial support 4.4
Notes
Notes Older versions of the specification treat absolute positioned children as though they are a 0 by 0 flex item. Later specification versions take the children out of the flow and set their positions based on align and justify properties. Chrome implements the new behavior beginning with Chrome 52.
Full support Yes
Prefixed
Prefixed Requires the vendor prefix: -webkit-
Chrome Android Full support 52
Full support 52
Partial support 29
Notes
Notes Older versions of the specification treat absolute positioned children as though they are a 0 by 0 flex item. Later specification versions take the children out of the flow and set their positions based on align and justify properties. Chrome implements the new behavior beginning with Chrome 52.
Full support 25
Prefixed
Prefixed Requires the vendor prefix: -webkit-
Edge Mobile Full support Yes
Full support Yes
Full support Yes
Prefixed
Prefixed Requires the vendor prefix: -webkit-
Firefox Android ? Opera Android Full support 12.1Safari iOS ? Samsung Internet Android Full support Yes
space-evenlyChrome Full support 60Edge No support NoFirefox Full support 52IE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoEdge Mobile No support NoFirefox Android Full support 52Opera Android No support NoSafari iOS No support NoSamsung Internet Android No support No
start and endChrome Partial support Partial
Notes
Partial support Partial
Notes
Notes This value is recognized, but has no effect.
Edge No support NoFirefox Full support YesIE No support NoOpera Partial support Partial
Notes
Partial support Partial
Notes
Notes This value is recognized, but has no effect.
Safari ? WebView Android ? Chrome Android ? Edge Mobile ? Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android ?
left and rightChrome Partial support Partial
Notes
Partial support Partial
Notes
Notes This value is recognized, but has no effect.
Edge No support NoFirefox Full support 52
Full support 52
No support ? — 52
Notes
Notes This value is recognized, but has no effect.
IE Partial support Partial
Notes
Partial support Partial
Notes
Notes This value is recognized, but has no effect.
Opera Partial support Partial
Notes
Partial support Partial
Notes
Notes This value is recognized, but has no effect.
Safari ? WebView Android ? Chrome Android ? Edge Mobile ? Firefox Android Full support 52
Full support 52
No support ? — 52
Notes
Notes This value is recognized, but has no effect.
Opera Android ? Safari iOS ? Samsung Internet Android ?
baselineChrome Full support 57Edge No support NoFirefox No support ? — 60
Notes
No support ? — 60
Notes
Notes justify-content no longer accepts baseline values
IE No support NoOpera ? Safari ? WebView Android ? Chrome Android ? Edge Mobile No support NoFirefox Android No support ? — 60
Notes
No support ? — 60
Notes
Notes justify-content no longer accepts baseline values
Opera Android ? Safari iOS ? Samsung Internet Android ?
first baseline and last baselineChrome No support NoEdge No support NoFirefox No support 52 — 60
Notes
No support 52 — 60
Notes
Notes justify-content no longer accepts baseline values
IE No support NoOpera No support NoSafari ? WebView Android ? Chrome Android ? Edge Mobile No support NoFirefox Android No support 52 — 60
Notes
No support 52 — 60
Notes
Notes justify-content no longer accepts baseline values
Opera Android ? Safari iOS ? Samsung Internet Android No support No
stretchChrome Full support 57Edge No support NoFirefox Full support 52IE No support NoOpera Full support 44Safari ? WebView Android ? Chrome Android ? Edge Mobile No support NoFirefox Android Full support 52Opera Android ? Safari iOS ? Samsung Internet Android ?
safe and unsafeChrome No support NoEdge No support NoFirefox Full support 63IE No support NoOpera No support NoSafari ? WebView Android ? Chrome Android ? Edge Mobile No support NoFirefox Android Full support 63Opera Android ? Safari iOS ? Samsung Internet Android No support No

Legend

Full support  
Full support
Partial support  
Partial support
No support  
No support
Compatibility unknown  
Compatibility unknown
See implementation notes.
See implementation notes.
User must explicitly enable this feature.
User must explicitly enable this feature.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

Support in Grid layout

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 57Edge Full support 16Firefox Full support 52IE ? Opera Full support 44Safari Full support 10.1WebView Android Full support 57Chrome Android Full support 52Edge Mobile Full support YesFirefox Android Full support 52Opera Android Full support 44Safari iOS Full support 10.3Samsung Internet Android Full support 6.2

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

See also