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/CSS

flex value

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.

Syntax

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

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;
}

Specifications

Specification	Status	Comment
CSS Grid Layout The definition of '<flex>' in that specification.	Candidate Recommendation	Initial definition.

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
`<flex>`	29	12	40	10	28	10.1

	Mobile
	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`<flex>`	57	29	40	28	10.3	2.0