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Summary

The margin CSS property sets the margin for all four sides. It is a shorthand to avoid setting each side separately with the other margin properties: margin-top, margin-right, margin-bottom and margin-left.

Negative values are also allowed.

Initial valueas each of the properties of the shorthand:
Applies toall elements, except elements with table display types other than table-caption, table and inline-table. It also applies to ::first-letter.
Inheritedno
Percentagesrefer to the width of the containing block
Mediavisual
Computed valueas each of the properties of the shorthand:
  • margin-bottom: the percentage as specified or the absolute length
  • margin-left: the percentage as specified or the absolute length
  • margin-right: the percentage as specified or the absolute length
  • margin-top: the percentage as specified or the absolute length
Animatableyes, as a length
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Syntax

/* Apply to all four sides */
margin: 1em;

/* vertical | horizontal */
margin: 5% auto;

/* top | horizontal | bottom */
margin: 1em auto 2em; 

/* top | right | bottom | left */
margin: 2px 1em 0 auto;

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

Values

Accepts one, two, three or four values of the following:

<length>
Specifies a fixed width. Negative Values are allowed. See for <length> possible units.
<percentage>
A <percentage> relative to the width of the containing block. Negative values are allowed.
auto
auto is replaced by some suitable value, e.g. it can be used for centering of blocks.
div { width:50%;  margin:0 auto; } centers the div container horizontally.
  • One single value applies to all four sides.
  • Two values apply first to top and bottom, the second one to left and right.
  • Three values apply first to top, second to left and right and third to bottom.
  • Four values apply to top, right, bottom and left in that order (clockwise).

Formal syntax

[ <length> | <percentage> | auto ]{1,4}

Examples

Simple example

HTML

<div class="ex1">
  margin:     auto;
  background: gold;
  width:      66%;
</div>
<div class="ex2">
  margin:     20px 0 0 -20px;
  background: gold;
  width:      66%;
</div>

CSS

.ex1 {
  margin: auto;
  background: gold;
  width: 66%;
}
.ex2 {
  margin: 20px 0px 0 -20px;
  background: gold;
  width: 66%;
}

Another example

margin: 5%;                /* all sides 5% margin */

margin: 10px;              /* all sides 10px margin */

margin: 1.6em 20px;        /* top and bottom 1.6em, left and right 20px margin */

margin: 10px 3% 1em;       /* top 10px, left and right 3%, bottom 1em margin */

margin: 10px 3px 30px 5px; /* top 10px, right 3px, bottom 30px, left 5px margin */

margin: 1em auto;          /* 1em margin on top and bottom, box is horizontally centered */

margin: auto;              /* box is horizontally centered, 0 margin on top and bottom */

Horizontal centering with margin: 0 auto;

To center something horizontally in modern browsers, use display: flex; justify-content: center; .

However, in older browsers like IE8-9, these are not available. In order to center an element inside its parent, use margin: 0 auto;

Specifications

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

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 1.0 1.0 (1.7 or earlier) 3.0 3.5 1.0 (85)
auto value 1.0 1.0 (1.7 or earlier) 6.0 (strict mode) 3.5 1.0 (85)
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 1.0 1.0 (1) 6.0 6.0 1.0

See also