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The margin-bottom CSS property sets the margin area on the bottom of an element. A positive value will place it farther than normal from its neighbors, while a negative value will place it closer.

The effect of the CSS margin-bottom property on the element box

This property has no effect on non-replaced inline elements, such as <span> or <code>.


/* <length> values */
margin-bottom: 10px;  /* An absolute length */
margin-bottom: 1em;   /* relative to the text size */
margin-bottom: 5%;    /* relative to the nearest block container's width */

/* Keyword values */
margin-bottom: auto;

/* Global values */
margin-bottom: inherit;
margin-bottom: initial;
margin-bottom: unset;

The margin-bottom property is specified as the keyword auto, or a <length>, or a <percentage>. Its value can be positive, zero, or negative.


The size of the margin as a fixed value.
The size of the margin as a percentage, relative to the width of the containing block.
The browser selects a suitable value to use. See margin.

Formal syntax

<length> | <percentage> | auto



<div class="container">
<div class="box0">Box 0</div>
<div class="box1">Box 1</div>
<div class="box2">Box one's negative margin pulls me up</div>


CSS for divs to set margin-bottom and height

.box0 {
.box1 {
.box2 {
    border:1px dashed black;
    border-width:1px 0;

Some definitions for container and divs so margins' effects can be seen more clearly

.container {
    border:1px solid black;
div {


Specification Status Comment
CSS Basic Box Model
The definition of 'margin-bottom' in that specification.
Working Draft No significant change
CSS Transitions
The definition of 'margin-bottom' in that specification.
Working Draft Defines margin-bottom as animatable.
CSS Level 2 (Revision 1)
The definition of 'margin-bottom' in that specification.
Recommendation Removes its effect on inline elements.
CSS Level 1
The definition of 'margin-bottom' in that specification.
Recommendation Initial definition

Initial value0
Applies toall elements, except elements with table display types other than table-caption, table and inline-table. It also applies to ::first-letter.
Percentagesrefer to the width of the containing block
Computed valuethe percentage as specified or the absolute length
Animation typea length
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support112133.51
auto1 ?1613.51
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support1 ? Yes461 ?
auto ? ? ?4 ? ? ?

1. The auto value is not supported in quirks mode.

Document Tags and Contributors

Last updated by: mfluehr,