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The max-height CSS property sets the maximum height of an element. It prevents the used value of the height property from becoming larger than the value specified for max-height.

max-height overrides height, but min-height overrides max-height.

Syntax

/* <length> value */
max-height: 3.5em;

/* <percentage> value */
max-height: 75%;

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

/* Global values */
max-height: inherit;
max-height: initial;
max-height: unset;

Values

<length>
The maximum height, expressed as a <length>.
<percentage>
The maximum height, expressed as a <percentage> of the containing block's height. If the height of the containing block is not specified explicitly, the percentage value is treated as zero.

Keyword values

none
The height has no maximum value.
max-content
The intrinsic preferred height.
min-content
The intrinsic minimum height.
fill-available
The containing block's height minus the vertical margin, border, and padding. (Note that some browsers implement an ancient name for this keyword, available.)
fit-content
The same as max-content.

Formal syntax

<length> | <percentage> | none | max-content | min-content | fit-content | fill-available

Examples

table { max-height: 75%; }

form { max-height: none; }

Accessibility concerns

Ensure that elements set with a max-height are not truncated and/or do not obscure other content when the page is zoomed to increase text size. 

Specifications

Specification Status Comment
CSS Intrinsic & Extrinsic Sizing Module Level 3
The definition of 'max-height' in that specification.
Working Draft Adds the max-content, min-content, fit-content, and fill-available keywords. (Both CSS3 Box and CSS3 Writing Modes drafts used to define these keywords, but are superseded by this spec.)
CSS Transitions
The definition of 'max-height' in that specification.
Working Draft Defines max-height as animatable.
CSS Level 2 (Revision 1)
The definition of 'max-height' in that specification.
Recommendation Initial definition.

Initial valuenone
Applies toall elements but non-replaced inline elements, table columns, and column groups
Inheritedno
PercentagesThe percentage is calculated with respect to the height of the generated box's containing block. If the height of the containing block is not specified explicitly (i.e., it depends on content height), and this element is not absolutely positioned, the percentage value is treated as none.
Mediavisual
Computed valuethe percentage as specified or the absolute length or none
Animation typea length, percentage or calc();
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 1Edge Full support 12Firefox Full support 1
Notes
Full support 1
Notes
Notes CSS 2.1 leaves the behavior of max-height with table undefined. Firefox supports applying max-height to table elements.
IE Full support 7Opera Full support 7
Notes
Full support 7
Notes
Notes CSS 2.1 leaves the behavior of max-height with table undefined. Opera supports applying max-height to table elements.
Safari Full support 1WebView Android ? Chrome Android ? Edge Mobile Full support YesFirefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android ?
fit-content, max-content, and min-content
Experimental
Chrome No support No
Notes
No support No
Notes
Notes Chrome implements an earlier proposal for setting height to an intrinsic height: the keywords intrinsic (instead of max-content), and min-intrinsic (instead of min-content). There is no equivalent for fill-available or fit-content.
Edge No support NoFirefox Partial support 3
Prefixed Notes
Partial support 3
Prefixed Notes
Prefixed Requires the vendor prefix: -moz-
Notes Firefox implements the definitions given in CSS3 Basic Box. This defines available and not fit-available. Also, the definition of fit-content is simpler than in CSS3 Sizing.
IE No support NoOpera No support NoSafari Full support 9
Notes
Full support 9
Notes
Notes Safari implements an earlier proposal for setting height to an intrinsic height: the keywords intrinsic (instead of max-content), and min-intrinsic (instead of min-content). There is no equivalent for fill-available or fit-content.
WebView Android ? Chrome Android ? Edge Mobile No support NoFirefox Android ? Opera Android ? Safari iOS Full support 9
Notes
Full support 9
Notes
Notes Safari implements an earlier proposal for setting height to an intrinsic height: the keywords intrinsic (instead of max-content), and min-intrinsic (instead of min-content). There is no equivalent for fill-available or fit-content.
Samsung Internet Android No support No
fill-available
Experimental
Chrome No support NoEdge No support NoFirefox No support NoIE No support NoOpera No support NoSafari No support NoWebView Android ? Chrome Android ? Edge Mobile No support NoFirefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android No support No

Legend

Full support  
Full support
Partial support  
Partial support
No support  
No support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
See implementation notes.
See implementation notes.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

See also