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The column-width CSS property specifies the minimum column width. The number of columns will be the maximum number of columns that can fit without any column having a width less than the column-width value. The actual column width may be smaller than the value of column-width if the width of the container is smaller.

/* Keyword value */
column-width: auto;

/* Different <length> values */
column-width: 6px;
column-width: 25em;
column-width: 0.3vw;

/* Global values */
column-width: inherit;
column-width: initial;
column-width: unset;

This allows you to achieve scalable designs that fit different screen sizes. Especially in presence of the column-count CSS property which has precedence, to set an exact column width, all length values must be specified. In horizontal text these are width, column-width, column-gap, and column-rule-width.

Initial valueauto
Applies toBlock containers except table wrapper boxes
Computed valuethe absolute length, zero or larger
Animation typea length
Canonical orderper grammar



Is a <length> value giving a hint of the optimal width of the column. The actual column width may be wider (to fill the available space), or narrower (only if the available space is smaller than the specified column width). The length must be strictly positive or the declaration is invalid.
Is a keyword indicating that the width of the column should be determined by other CSS properties, like column-count.

Formal syntax

<length> | auto


HTML Content

<div class="content-box">
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat.

CSS Content

.content-box {
  border: 10px solid #0ff;

  /* Chrome, Safari, Opera prefix */
  -webkit-column-width: 100px;

  /* Mozilla Firefox prefix */
  -moz-column-width: 100px;

  column-width: 100px;


Specification Status Comment
CSS Writing Modes Module Level 3
The definition of 'column-width' in that specification.
Candidate Recommendation Adds intrinsic sizes via the keywords min-content, max-content, fill-available and fit-content.
CSS Multi-column Layout Module
The definition of 'column-width' in that specification.
Candidate Recommendation Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support (Yes)-webkit
1.5 (1.8)-moz
50.0 (50.0)[2]
10 11.10 3.0 (522)-webkit
Intrinsic sizes No support ? No support No support No support No support
on display: table-caption (Yes) (Yes) 37 (37) (Yes) (Yes) (Yes)
Feature Android Android Webview Edge Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support (Yes) ?
1.0 (1.8)-moz
50.0 (50.0)[2]
(Yes) (Yes) (Yes) ?
Intrinsic sizes No support ? ? No support No support No support No support ?
on display: table-caption (Yes) 50.0 (Yes) 37.0 (37) (Yes) (Yes) (Yes) 50.0

[1]  Unprefixed as of Chrome 50.

[2] Unprefixed as of Gecko 52, with prefixed aliases still available.