CSS - max-block-size



HTML Content

<p class="exampleText">Example text</p>

CSS Content

.exampleText {
  writing-mode: vertical-rl;
  background-color: yellow;
  block-size: 100%;
  max-block-size: 200px;


/* <length> values */
max-block-size: 300px;
max-block-size: 25em;

/* <percentage> values */
max-block-size: 75%;

/* Keyword values */
max-block-size: none;
max-block-size: max-content;
max-block-size: min-content;
max-block-size: fit-content;
max-block-size: fill-available;

/* Global values */
max-block-size: inherit;
max-block-size: initial;
max-block-size: unset;


The max-block-size property takes the same values as the max-width and max-height properties.

Formal syntax

<a href="css/max-width" title="&lt;length&gt; | &lt;percentage&gt; | none | max-content | min-content | fit-content | fill-available"><'max-width'></a>


The max-block-size CSS property defines the horizontal or vertical maximal size of an element's block depending on its writing mode. It corresponds to the max-width or the max-height property, depending on the value defined for writing-mode. If the writing mode is vertically oriented, the value of max-block-size relates to the maximal width of the element, otherwise it relates to the maximal height of the element. It relates to max-inline-size, which defines the other dimension of the element.

Initial value0
Applies tosame as width and height
Percentagesblock-size of containing block
Computed valuesame as max-width and max-height
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Browser Compatibility  

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support Not supported 41.0 (41.0)[1] Not supported Not supported Not supported
Feature Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support Not supported 41.0 (41.0)[1] Not supported Not supported Not supported

[1] Available since Gecko 38, but behind the preference layout.css.vertical-text.enabled, then disabled by default.

See Also  


Specification Status Comment
CSS Logical Properties Level 1
The definition of 'max-block-size' in that specification.
Editor's Draft Initial definition


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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.

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