Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2020.

The <flex> CSS data type denotes a flexible length within a grid container. It is used in grid-template-columns, grid-template-rows and other related properties.


The <flex> data type is specified as a <number> followed by the unit fr. The fr unit represents a fraction of the leftover space in the grid container. As with all CSS dimensions, there is no space between the unit and the number.


Examples of correct values for the fr data type

1fr    /* Using an integer value */
2.5fr  /* Using a float value */

Example of use in a tracklisting for CSS grid layout

.grid {
  display: grid;
  grid-template-columns: 1fr 1fr 2.5fr 1.5fr;


CSS Grid Layout Module Level 2
# fr-unit

Browser compatibility

BCD tables only load in the browser

See also