Margin

Overview

Use margin utilities to control the outer space around elements. Margin utilities are built from a default Sass map ranging from .25rem to 3rem. Use utilities like .m-3 and .m-5 to control the margin on all sides of an element:

<div class="m-3">.m-3</div>
<div class="m-5">.m-5</div>

Notation

Margin utilities that apply to all breakpoints, from xs to 2xl, have no breakpoint abbreviation in them. This is because those classes are applied from min-width: 0 and up, and thus are not bound by a media query. The remaining breakpoints, however, do include a breakpoint abbreviation.

The classes are named using the format {property}{sides}-{size} for xs and {property}{sides}-{breakpoint}-{size} for sm, md, lg, xl, and 2xl.

Where property is:

• m - for classes that set margin

Where sides is one of:

• t - for classes that set margin-top
• b - for classes that set margin-bottom
• s - (start) for classes that set margin-left in LTR, margin-right in RTL
• e - (end) for classes that set margin-right in LTR, margin-left in RTL
• x - for classes that set both *-left and *-right
• y - for classes that set both *-top and *-bottom
• blank - for classes that set a margin on all 4 sides of the element

Where size is one of:

• 0 - for classes that eliminate the margin by setting it to 0
• 1 - (by default) for classes that set the margin to $spacer * .25
• 2 - (by default) for classes that set the margin to $spacer * .5
• 3 - (by default) for classes that set the margin to $spacer
• 4 - (by default) for classes that set the margin to $spacer * 1.5
• 5 - (by default) for classes that set the margin to $spacer * 3
• auto - for classes that set the margin to auto

(You can add more sizes by adding entries to the $spacers Sass map variable.)

Examples

Single side

Use utilities like .mt-3, .me-2, .mb-4, and .ms-1 to control the margin on one side of an element:

<div class="mt-4">.mt-4</div>
<div class="me-4">.me-4</div>
<div class="mb-4">.mb-4</div>
<div class="ms-4">.ms-4</div>

Horizontal margin

Use utilities like .mx-3 and .mx-5 to control the horizontal margin of an element:

<div class="mx-3">.mx-3</div>
<div class="mx-5">.mx-5</div>

Vertical margin

Use utilities like .my-3 and .my-5 to control the vertical margin of an element:

<div class="my-3">.my-3</div>
<div class="my-5">.my-5</div>

Horizontal centering

Bootstrap includes an .mx-auto class for horizontally centering fixed-width block level content—that is, content that has display: block and a width set—by setting the horizontal margins to auto.

<div class="mx-auto" style="width: 200px;">
  Centered element
</div>

Negative margin

In CSS, margin properties can utilize negative values (padding cannot). These negative margins are disabled by default, but can be enabled in Sass by setting $enable-negative-margins: true.

The syntax is nearly the same as the default, positive margin utilities, but with the addition of n before the requested size. Here’s an example class that’s the opposite of .mt-1:

.mt-n1 {
  margin-top: -0.25rem !important;
}

Responsive

All margin utilities are responsive and include all breakpoints.

• .m-0 through .m-5 and .m-auto
• .m-sm-0 through .m-sm-5 and .m-sm-auto
• .m-md-0 through .m-md-5 and .m-md-auto
• .m-lg-0 through .m-lg-5 and .m-lg-auto
• .m-xl-0 through .m-xl-5 and .m-xl-auto
• .m-2xl-0 through .m-2xl-5 and .m-2xl-auto

CSS

Sass utilities API

Margin utilities are declared in our utilities API in scss/_utilities.scss. Learn how to use the utilities API.

"margin": (
  responsive: true,
  property: margin,
  class: m,
  values: map.merge($spacers, (auto: auto))
),
"margin-x": (
  responsive: true,
  property: margin-right margin-left,
  class: mx,
  values: map.merge($spacers, (auto: auto))
),
"margin-y": (
  responsive: true,
  property: margin-top margin-bottom,
  class: my,
  values: map.merge($spacers, (auto: auto))
),
"margin-top": (
  responsive: true,
  property: margin-top,
  class: mt,
  values: map.merge($spacers, (auto: auto))
),
"margin-end": (
  responsive: true,
  property: margin-right,
  class: me,
  values: map.merge($spacers, (auto: auto))
),
"margin-bottom": (
  responsive: true,
  property: margin-bottom,
  class: mb,
  values: map.merge($spacers, (auto: auto))
),
"margin-start": (
  responsive: true,
  property: margin-left,
  class: ms,
  values: map.merge($spacers, (auto: auto))
),