fit-content

The fit-content() CSS function clamps a given size to an available size according to the formula min(maximum size, max(minimum size, argument)).

The function can be used as a track size in CSS Grid properties, where the maximum size is defined by max-content and the minimum size by auto, which is calculated similar to auto (i.e. minmax(auto, max-content)), except that the track size is clamped at argument if it is greater than the auto minimum.

It can also be used as layed out box size for width, height, min-width, min-height, max-width and max-height, where the maximum size refers to the maximum content size and the minimum size to the minimum content size.

Syntax

/* <length> values */
fit-content(200px)
fit-content(5cm)
fit-content(30vw)
fit-content(100ch)

/* <percentage> value */
fit-content(40%)

Values

<length>

An absolute length.

<percentage>

A percentage relative to the available space in the given axis.

In grid properties it is relative to the inline size of the grid container in column tracks and to the block size of the grid container for row tracks. Otherwise it is relative to the available inline size or block size of the layed out box depending on the writing mode.

Formal syntax

fit-content( [ <length> | <percentage> ] )

Example

CSS content

#container {
  display: grid;
  grid-template-columns: fit-content(300px) fit-content(300px) 1fr;
  grid-gap: 5px;
  box-sizing: border-box;
  height: 200px;
  width: 100%;
  background-color: #8cffa0;
  padding: 10px;
}

#container > div {
  background-color: #8ca0ff;
  padding: 5px;
}

HTML content

<div id="container">
  <div>Item as wide as the content.</div>
  <div>
    Item with more text in it. Because the contents of it are
    wider than the maximum width, it is clamped at 300 pixels.
  </div>
  <div>Flexible item</div>
</div>

Result

Specifications

Specification	Status	Comment
CSS Intrinsic & Extrinsic Sizing Module Level 3 The definition of 'fit-content()' in that specification.	Working Draft	Defines the function as layed out box size for width, height, min-width, min-height, max-width and max-height.
CSS Grid Layout The definition of 'fit-content()' in that specification.	Candidate Recommendation	Defines the function when used as a track size.

Browser compatibility

[1] Implemented behind the experimental Web Platform features flag in chrome://flags since Chrome 29.0 and Opera 28.0.

[2] Implemented behind the preference layout.css.grid.enabled, defaulting to false since Gecko 51.0 (Firefox 51.0 / Thunderbird 51.0 / SeaMonkey 2.48).

[3] The fit-content() function is not implemented yet for the width and height related properties. See bug 1312588.