Warning: This is a property of the original CSS Flexible Box Layout Module standard which is being replaced by a new standard.

See Flexbox for more information.

The CSS box-ordinal-group property assigns the flexbox's child elements to an ordinal group. See Flexbox for more about the properties of flexbox elements.

/* <integer> values */
box-ordinal-group: 1;
box-ordinal-group: 5;

/* Global values */
box-ordinal-group: inherit;
box-ordinal-group: initial;
box-ordinal-group: unset;

Ordinal groups may be used in conjunction with the box-direction property to control the order in which the direct children of a box appear. When the computed box-direction is normal, a box will display its elements starting from the lowest numbered ordinal group and ensure that those elements appear to the left (for horizontal boxes) or at the top (for vertical boxes) of the container. Elements with the same ordinal group are flowed in the order they appear in the source document tree. In the reverse direction, the ordinal groups are examined in the same order, except the elements appear reversed.

Initial value1
Applies tochildren of box elements
Computed valueas specified
Animation typediscrete
Canonical orderthe unique non-ambiguous order defined by the formal grammar


Any positive integer.

Formal syntax



Flexible Box Layout Module (W3C Working Draft)

Note: The current state of this specification does not reflect Mozilla's or WebKit's implementation.

Old Flexible Box Layout Module

Note: WebKit and Mozilla's implementations reflect this version of the specification.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes)-webkit (Yes)-webkit (Yes)-moz[1] No support (Yes)-webkit 1.1-khtml
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? ? (Yes)-webkit ? No support ? 1.0-webkit

[1] In addition to the -moz prefixed 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.

See also

box-flex, box-flex-group, box-pack

Document Tags and Contributors

 Last updated by: wbamberg,