The flex-grow CSS property sets the flex grow factor of a flex item's main size.


/* <number> values */
flex-grow: 3;
flex-grow: 0.6;

/* Global values */
flex-grow: inherit;
flex-grow: initial;
flex-grow: unset;

The flex-grow property is specified as a single <number>.


See <number>. Negative values are invalid. Defaults to 0.


This property specifies how much of the remaining space in the flex container should be assigned to the item (the flex grow factor).

The main size is either width or height of the item which is dependent on the flex-direction value.

The remaining space is the size of the flex container minus the size of all flex items' sizes together. If all sibling items have the same flex grow factor, then all items will receive the same share of remaining space, otherwise it is distributed according to the ratio defined by the different flex grow factors.

flex-grow is used alongside the other flex properties flex-shrink and flex-basis, and normally defined using the flex shorthand to ensure all values are set.

Formal definition

Initial value0
Applies toflex items, including in-flow pseudo-elements
Computed valueas specified
Animation typea number

Formal syntax



Setting flex item grow factor


<h4>This is a Flex-Grow</h4>
<h5>A,B,C and F are flex-grow:1 . D and E are flex-grow:2 .</h5>
<div id="content">
  <div class="box" style="background-color:red;">A</div>
  <div class="box" style="background-color:lightblue;">B</div>
  <div class="box" style="background-color:yellow;">C</div>
  <div class="box1" style="background-color:brown;">D</div>
  <div class="box1" style="background-color:lightgreen;">E</div>
  <div class="box" style="background-color:brown;">F</div>


#content {
  display: flex;

  justify-content: space-around;
  flex-flow: row wrap;
  align-items: stretch;

.box {
  flex-grow: 1;
  border: 3px solid rgba(0,0,0,.2);

.box1 {
  flex-grow: 2;
  border: 3px solid rgba(0,0,0,.2);



Specification Status Comment
CSS Flexible Box Layout Module
The definition of 'flex-grow' in that specification.
Candidate Recommendation Initial definition

Browser compatibility

BCD tables only load in the browser

See also