Containers

Containers are the most basic layout element and are required when using our default grid system. Choose from a responsive, fixed-width container (meaning its max-width changes at each breakpoint) or fluid-width (meaning it’s 100% wide all the time).

While containers can be nested, most layouts do not require a nested container.

<div class="container">
	<!-- Content here -->
</div>

Use .container-fluid for a full width container, spanning the entire width of the viewport.

<div class="container-fluid">
	...
</div>

Responsive breakpoints

Since Bootstrap is developed to be mobile first, we use a handful of media queries to create sensible breakpoints for our layouts and interfaces. These breakpoints are mostly based on minimum viewport widths and allow us to scale up elements as the viewport changes.

Bootstrap primarily uses the following media query ranges—or breakpoints—in our source Sass files for our layout, grid system, and components.

// Extra small devices (portrait phones, less than 576px)
// No media query since this is the default in Bootstrap

// Small devices (landscape phones, 576px and up)
@media (min-width: 576px) { ... }

// Medium devices (tablets, 768px and up)
@media (min-width: 768px) { ... }

// Large devices (desktops, 992px and up)
@media (min-width: 992px) { ... }

// Extra large devices (large desktops, 1280px and up)
@media (min-width: 1280px) { ... }

Since we write our source CSS in Sass, all our media queries are available via Sass function:

.some-class {
	@media(min-width: breakpoint-min(md)) {
		display: block;
	}
}

We occasionally use media queries that go in the other direction (the given screen size or smaller):

// Extra small devices (portrait phones, less than 576px)
@media (max-width: 575px) { ... }

// Small devices (landscape phones, less than 768px)
@media (max-width: 767px) { ... }

// Medium devices (tablets, less than 992px)
@media (max-width: 991px) { ... }

// Large devices (desktops, less than 1200px)
@media (max-width: 1199px) { ... }

// Extra large devices (large desktops)
// No media query since the extra-large breakpoint has no upper bound on its width

Once again, these media queries are also available via Sass function:

.some-class {
	@media(min-width: breakpoint-max(md)) {
		...
	}
}

There are also media queries in Sass mixins:

@include media-breakpoint-up(xl) { ... }
@include media-breakpoint-down(lg) { ... }
@include media-breakpoint-only(xl) { ... }
@include media-breakpoint-between(md, xl) { ... }

Grid

Bootstrap’s grid system uses a series of containers, rows, and columns to layout and align content. It’s built with flexbox and is fully responsive. Below is an example and an in-depth look at how the grid comes together.

New to or unfamiliar with flexbox? Read this CSS Tricks flexbox guide for background, terminology, guidelines, and code snippets.

One of three columns
One of three columns
One of three columns
<div class="container">
	<div class="row">
		<div class="col-sm">
			One of three columns
		</div>
		<div class="col-sm">
			One of three columns
		</div>
		<div class="col-sm">
			One of three columns
		</div>
	</div>
</div>

The above example creates three equal-width columns on small, medium, large, and extra large devices using our predefined grid classes. Those columns are centered in the page with the parent .container.

Breaking it down, here’s how it works:

Be aware of the limitations and bugs around flexbox, like the inability to use some HTML elements as flex containers.

Grid options

While Bootstrap uses ems or rems for defining most sizes, pxs are used for grid breakpoints and container widths. This is because the viewport width is in pixels and does not change with the font size.

See how aspects of the Bootstrap grid system work across multiple devices with a handy table.

Extra small
<576px
Small
≥576px
Medium
≥768px
Large
≥992px
Extra large
≥1200px
Max container width None (auto) 540px 720px 960px 1140px
Class prefix .col- .col-sm- .col-md- .col-lg- .col-xl-
# of columns 12
Gutter width 30px (15px on each side of a column)
Nestable Yes
Column ordering Yes

Auto-layout columns

Utilize breakpoint-specific column classes for easy column sizing without an explicit numbered class like .col-sm-6.

Equal-width

For example, here are two grid layouts that apply to every device and viewport, from xs to xl. Add any number of unit-less classes for each breakpoint you need and every column will be the same width.

1 of 2
2 of 2
1 of 3
2 of 3
3 of 3
<div class="container">
	<div class="row">
		<div class="col">
			1 of 2
		</div>
		<div class="col">
			2 of 2
		</div>
	</div>
	<div class="row">
		<div class="col">
			1 of 3
		</div>
		<div class="col">
			2 of 3
		</div>
		<div class="col">
			3 of 3
		</div>
	</div>
</div>

Equal-width columns can be broken into multiple lines, but there was a Safari flexbox bug that prevented this from working without an explicit flex-basis or border. There are workarounds for older browser versions, but they shouldn’t be necessary if you’re up-to-date.

Column
Column
Column
Column
<div class="container">
	<div class="row">
		<div class="col">Column</div>
		<div class="col">Column</div>
		<div class="w-100"></div>
		<div class="col">Column</div>
		<div class="col">Column</div>
	</div>
</div>

Setting one column width

Auto-layout for flexbox grid columns also means you can set the width of one column and have the sibling columns automatically resize around it. You may use predefined grid classes (as shown below), grid mixins, or inline widths. Note that the other columns will resize no matter the width of the center column.

1 of 3
2 of 3 (wider)
3 of 3
1 of 3
2 of 3 (wider)
3 of 3
<div class="container">
	<div class="row">
		<div class="col">
			1 of 3
		</div>
		<div class="col-12">
			2 of 3 (wider)
		</div>
		<div class="col">
			3 of 3
		</div>
	</div>
	<div class="row">
		<div class="col">
			1 of 3
		</div>
		<div class="col-10">
			2 of 3 (wider)
		</div>
		<div class="col">
			3 of 3
		</div>
	</div>
</div>

Variable width content

Use col-{breakpoint}-auto classes to size columns based on the natural width of their content.

1 of 3
Variable width content
3 of 3
1 of 3
Variable width content
3 of 3
<div class="container">
	<div class="row justify-content-md-center">
		<div class="col col-lg-2">
			1 of 3
		</div>
		<div class="col-md-auto">
			Variable width content
		</div>
		<div class="col col-lg-2">
			3 of 3
		</div>
	</div>
	<div class="row">
		<div class="col">
			1 of 3
		</div>
		<div class="col-md-auto">
			Variable width content
		</div>
		<div class="col col-lg-2">
			3 of 3
		</div>
	</div>
</div>

Equal-width multi-row

Create equal-width columns that span multiple rows by inserting a .w-100 where you want the columns to break to a new line. Make the breaks responsive by mixing the .w-100 with some responsive display utilities.

.col
.col
.col
.col
<div class="row">
	<div class="col">.col</div>
	<div class="col">.col</div>
	<div class="w-100"></div>
	<div class="col">.col</div>
	<div class="col">.col</div>
</div>

Responsive classes

Bootstrap’s grid includes five tiers of predefined classes for building complex responsive layouts. Customize the size of your columns on extra small, small, medium, large, or extra large devices however you see fit.

All breakpoints

For grids that are the same from the smallest of devices to the largest, use the .col and .col-* classes. Specify a numbered class when you need a particularly sized column; otherwise, feel free to stick to .col.

.col
.col
.col
.col
.col-16
.col-8
<div class="row">
	<div class="col">.col</div>
	<div class="col">.col</div>
	<div class="col">.col</div>
	<div class="col">.col</div>
</div>
<div class="row">
	<div class="col-16">.col-16</div>
	<div class="col-8">.col-8</div>
</div>

Stacked to horizontal

Using a single set of .col-sm-* classes, you can create a basic grid system that starts out stacked before becoming horizontal with at the small breakpoint (sm).

.col-sm-16
.col-sm-8
.col-sm
.col-sm
.col-sm
<div class="row">
		<div class="col-sm-8">.col-sm-16</div>
		<div class="col-sm-4">.col-sm-8</div>
	</div>
	<div class="row">
		<div class="col-sm">.col-sm</div>
		<div class="col-sm">.col-sm</div>
		<div class="col-sm">.col-sm</div>
	</div>

Mix and match

Don’t want your columns to simply stack in some grid tiers? Use a combination of different classes for each tier as needed. See the example below for a better idea of how it all works.

.col-24 .col-md-16
.col-12 .col-md-8
.col-12 .col-md-8
.col-12 .col-md-8
.col-12 .col-md-8
.col-12
.col-12
<!-- Stack the columns on mobile by making one full-width and the other half-width -->
<div class="row">
	<div class="col-24 col-md-16">.col-12 .col-md-16</div>
	<div class="col-12 col-md-8">.col-12 .col-md-8</div>
</div>
<!-- Columns start at 50% wide on mobile and bump up to 33.3% wide on desktop -->
<div class="row">
	<div class="col-12 col-md-8">.col-12 .col-md-8</div>
	<div class="col-12 col-md-8">.col-12 .col-md-8</div>
	<div class="col-12 col-md-8">.col-12 .col-md-8</div>
</div>
<!-- Columns are always 50% wide, on mobile and desktop -->
<div class="row">
	<div class="col-12">.col-12</div>
	<div class="col-12">.col-12</div>
</div>

Alignment

Use flexbox alignment utilities to vertically and horizontally align columns.

Vertical alignment

One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
One of three columns
<div class="container">
	<div class="row align-items-start">
		<div class="col">
			One of three columns
		</div>
		<div class="col">
			One of three columns
		</div>
		<div class="col">
			One of three columns
		</div>
	</div>
	<div class="row align-items-center">
		<div class="col">
			One of three columns
		</div>
		<div class="col">
			One of three columns
		</div>
		<div class="col">
			One of three columns
		</div>
	</div>
	<div class="row align-items-end">
		<div class="col">
			One of three columns
		</div>
		<div class="col">
			One of three columns
		</div>
		<div class="col">
			One of three columns
		</div>
	</div>
</div>

One of three columns
One of three columns
One of three columns
<div class="container">
	<div class="row">
		<div class="col align-self-start">
			One of three columns
		</div>
		<div class="col align-self-center">
			One of three columns
		</div>
		<div class="col align-self-end">
			One of three columns
		</div>
	</div>
</div>

Horizontal alignment

One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
One of two columns
<div class="container">
	<div class="row justify-content-start">
		<div class="col-8">
		 One of two columns
		</div>
		<div class="col-8">
		 One of two columns
		</div>
	</div>
	<div class="row justify-content-center">
		<div class="col-8">
		 One of two columns
		</div>
		<div class="col-8">
		 One of two columns
		</div>
	</div>
	<div class="row justify-content-end">
		<div class="col-8">
		 One of two columns
		</div>
		<div class="col-8">
		 One of two columns
		</div>
	</div>
	<div class="row justify-content-around">
		<div class="col-8">
		 One of two columns
		</div>
		<div class="col-8">
		 One of two columns
		</div>
	</div>
	<div class="row justify-content-between">
		<div class="col-8">
		 One of two columns
		</div>
		<div class="col-8">
		 One of two columns
		</div>
	</div>
</div>

No gutters

The gutters between columns in our predefined grid classes can be removed with .no-gutters. This removes the negative margins from .row and the horizontal padding from all immediate children columns.

Here’s the source code for creating these styles. Note that column overrides are scoped to only the first children columns and are targeted via attribute selector. While this generates a more specific selector, column padding can still be further customized with spacing utilities.

Need an edge-to-edge design? Drop the parent .container or .container-fluid.

.no-gutters {
	margin-right: 0;
	margin-left: 0;
	
	> .col,
	> [class*="col-"] {
		padding-right: 0;
		padding-left: 0;
	}
	}

In practice, here’s how it looks. Note you can continue to use this with all other predefined grid classes (including column widths, responsive tiers, reorders, and more).

.col-24 .col-sm-12 .col-md-16
.col-12 .col-md-8
<div class="row no-gutters">
	<div class="col-24 col-sm-12 col-md-16">.col-24 .col-sm-12 .col-md-16</div>
	<div class="col-12 col-md-8">.col-12 .col-md-8</div>
</div>

Line gutters

Line gutters has the same usege as no-gutters, so class is added to row. This removes default gutter spacing from all immediate children columns and add 1px margin-top and 1px padding-left.

.line-gutters {
	margin: -1px 0 0 -1px;

	& > .col,
	& > [class*="col-"] {
		margin-bottom: 0;
		margin-top: 1px;
		padding-left: 1px;
		padding-right: 0;
	}
}

.col-24 .col-sm-12 .col-md-6
.col-24 .col-sm-12 .col-md-6
.col-12 .col-md-6
.col-12 .col-md-6
<div class="row line-gutters">
    <div class="col-24 col-sm-12 col-md-6">.col-24 .col-sm-12 .col-md-6</div>
    <div class="col-24 col-sm-12 col-md-6">.col-24 .col-sm-12 .col-md-6</div>
    <div class="col-12 col-md-6">.col-12 .col-md-6</div>
    <div class="col-12 col-md-6">.col-12 .col-md-6</div>
</div>

Column wrapping

If more than 12 columns are placed within a single row, each group of extra columns will, as one unit, wrap onto a new line.

.col-18
.col-8
Since 18 + 8 = 26 > 24, this 8-column-wide div gets wrapped onto a new line as one contiguous unit.
.col-12
Subsequent columns continue along the new line.
<div class="row">
	<div class="col-18">.col-18</div>
	<div class="col-8">.col-8<br>Since 18 + 8 = 26 > 24, this 8-column-wide div gets wrapped onto a new line as one contiguous unit.</div>
	<div class="col-12">.col-12<br>Subsequent columns continue along the new line.</div>
</div>

Column breaks

Breaking columns to a new line in flexbox requires a small hack: add an element with width: 100% wherever you want to wrap your columns to a new line. Normally this is accomplished with multiple .rows, but not every implementation method can account for this.

.col-12 .col-sm-6
.col-12 .col-sm-6
.col-12 .col-sm-6
.col-12 .col-sm-6
<div class="row">
	<div class="col-12 col-sm-6">.col-12 .col-sm-6</div>
	<div class="col-12 col-sm-6">.col-12 .col-sm-6</div>

	<!-- Force next columns to break to new line -->
	<div class="w-100"></div>

	<div class="col-12 col-sm-6">.col-12 .col-sm-6</div>
	<div class="col-12 col-sm-6">.col-12 .col-sm-6</div>
</div>

You may also apply this break at specific breakpoints with our responsive display utilities.

.col-12 .col-sm-8
.col-12 .col-sm-8
.col-12 .col-sm-8
.col-12 .col-sm-8
<div class="row">
	<div class="col-12 col-sm-8">.col-12 .col-sm-8</div>
	<div class="col-12 col-sm-8">.col-12 .col-sm-8</div>
	
	<!-- Force next columns to break to new line at md breakpoint and up -->
	<div class="w-100 d-none d-md-block"></div>
	
	<div class="col-12 col-sm-8">.col-12 .col-sm-8</div>
	<div class="col-12 col-sm-8">.col-12 .col-sm-8</div>
</div>

Reordering

Reordering Order classes

Use .order- classes for controlling the visual order of your content. These classes are responsive, so you can set the order by breakpoint (e.g., .order-1.order-md-2). Includes support for 1 through 24 across all five grid tiers.

First, but unordered
Second, but last
Third, but first
<div class="container">
	<div class="row">
		<div class="col">
			First, but unordered
		</div>
		<div class="col order-12">
			Second, but last
		</div>
		<div class="col order-1">
			Third, but first
		</div>
	</div>
</div>

There are also responsive .order-first and .order-last classes that change the order of an element by applying order: -1 and order: 13 (order: $columns + 1), respectively. These classes can also be intermixed with the numbered .order-* classes as needed.

Offsetting columns

You can offset grid columns in two ways: our responsive .offset- grid classes and our margin utilities. Grid classes are sized to match columns while margins are more useful for quick layouts where the width of the offset is variable.

Offset classes

Move columns to the right using .offset-md-* classes. These classes increase the left margin of a column by * columns. For example, .offset-md-8 moves .col-md-8 over four columns.

.col-md-8
.col-md-16 .offset-md-16
.col-md-6 .offset-md-6
.col-md-6 .offset-md-6
.col-md-12 .offset-md-6
<div class="row">
	<div class="col-md-8">.col-md-8</div>
	<div class="col-md-8 offset-md-8">.col-md-8 .offset-md-8</div>
</div>
<div class="row">
	<div class="col-md-6 offset-md-6">.col-md-6 .offset-md-6</div>
	<div class="col-md-6 offset-md-6">.col-md-6 .offset-md-6</div>
</div>
<div class="row">
	<div class="col-md-12 offset-md-6">.col-md-12 .offset-md-6</div>
</div>

In addition to column clearing at responsive breakpoints, you may need to reset offsets. See this in action in the grid example.

.col-sm-10 .col-md-12
.col-sm-10 .offset-sm-4 .col-md-12 .offset-md-0
.col-sm-12 .col-md-10 .col-lg-12
.col-sm-12 .col-md-10 .offset-md-4 .col-lg-12 .offset-lg-0
<div class="row">
  <div class="col-sm-10 col-md-12">.col-sm-10 .col-md-12</div>
  <div class="col-sm-10 offset-sm-4 col-md-12 offset-md-0">.col-sm-10 .offset-sm-4 .col-md-12 .offset-md-0</div>
</div>
	
<div class="row">
  <div class="col-sm-12 col-md-10 col-lg-12">.col-sm-12 .col-md-10 .col-lg-12</div>
  <div class="col-sm-12 col-md-10 offset-md-4 col-lg-12 offset-lg-0">.col-sm-12 .col-md-10 .offset-md-4 .col-lg-12 .offset-lg-0</div>
</div>

Margin utilities

With the move to flexbox in v4, you can use margin utilities like .mr-auto to force sibling columns away from one another.

.col-md-8
.col-md-8 .ml-auto
.col-md-6 .ml-md-auto
.col-md-6 .ml-md-auto
.col-auto .mr-auto
.col-auto
<div class="row">
	<div class="col-md-8">.col-md-8</div>
	<div class="col-md-8 ml-auto">.col-md-8 .ml-auto</div>
</div>
<div class="row">
	<div class="col-md-6 ml-md-auto">.col-md-6 .ml-md-auto</div>
	<div class="col-md-6 ml-md-auto">.col-md-6 .ml-md-auto</div>
</div>
<div class="row">
	<div class="col-auto mr-auto">.col-auto .mr-auto</div>
	<div class="col-auto">.col-auto</div>
</div>

Nesting

To nest your content with the default grid, add a new .row and set of .col-sm-* columns within an existing .col-sm-* column. Nested rows should include a set of columns that add up to 12 or fewer (it is not required that you use all 12 available columns).

Level 1: .col-sm-18
Level 2: .col-16 .col-sm-12
Level 2: .col-8 .col-sm-12
<div class="row">
	<div class="col-sm-18">
		Level 1: .col-sm-18
		<div class="row">
		<div class="col-16 col-sm-12">
			Level 2: .col-16 .col-sm-12
		</div>
		<div class="col-8 col-sm-12">
			Level 2: .col-8 .col-sm-12
		</div>
		</div>
	</div>
</div>

Sass mixins

When using Bootstrap’s source Sass files, you have the option of using Sass variables and mixins to create custom, semantic, and responsive page layouts. Our predefined grid classes use these same variables and mixins to provide a whole suite of ready-to-use classes for fast responsive layouts.

Variables

Variables and maps determine the number of columns, the gutter width, and the media query point at which to begin floating columns. We use these to generate the predefined grid classes documented above, as well as for the custom mixins listed below.

$grid-columns:      12;
$grid-gutter-width: 30px;

$grid-breakpoints: (
	// Extra small screen / phone
	xs: 0,
	// Small screen / phone
	sm: 576px,
	// Medium screen / tablet
	md: 768px,
	// Large screen / desktop
	lg: 992px,
	// Extra large screen / wide desktop
	xl: 1200px
);

$container-max-widths: (
	sm: 540px,
	md: 720px,
	lg: 960px,
	xl: 1140px
);

Mixins

Mixins are used in conjunction with the grid variables to generate semantic CSS for individual grid columns.

// Creates a wrapper for a series of columns
@include make-row();

// Make the element grid-ready (applying everything but the width)
@include make-col-ready();
@include make-col($size, $columns: $grid-columns);

// Get fancy by offsetting, or changing the sort order
@include make-col-offset($size, $columns: $grid-columns);

Example usage

You can modify the variables to your own custom values, or just use the mixins with their default values. Here’s an example of using the default settings to create a two-column layout with a gap between.

.example-container {
	width: 800px;
	@include make-container();
}
	
.example-row {
	@include make-row();
}
	
.example-content-main {
	@include make-col-ready();
	
	@include media-breakpoint-up(sm) {
		@include make-col(6);
	}
	@include media-breakpoint-up(lg) {
		@include make-col(8);
	}
}
	
.example-content-secondary {
	@include make-col-ready();
	
	@include media-breakpoint-up(sm) {
		@include make-col(6);
	}
	@include media-breakpoint-up(lg) {
		@include make-col(4);
	}
}

Main content
Secondary content
<div class="example-container">
	<div class="example-row">
		<div class="example-content-main">Main content</div>
		<div class="example-content-secondary">Secondary content</div>
	</div>
</div>

Customizing the grid

Using our built-in grid Sass variables and maps, it’s possible to completely customize the predefined grid classes. Change the number of tiers, the media query dimensions, and the container widths—then recompile.

Columns and gutters

The number of grid columns can be modified via Sass variables. $grid-columns is used to generate the widths (in percent) of each individual column while $grid-gutter-width allows breakpoint-specific widths that are divided evenly across padding-left and padding-right for the column gutters.

$grid-columns: 12 !default;
$grid-gutter-width: 30px !default;

Grid tiers

Moving beyond the columns themselves, you may also customize the number of grid tiers. If you wanted just four grid tiers, you’d update the $grid-breakpoints and $container-max-widths to something like this:

$grid-breakpoints: (
	xs: 0,
	sm: 480px,
	md: 768px,
	lg: 1024px
);
	
$container-max-widths: (
	sm: 420px,
	md: 720px,
	lg: 960px
);

When making any changes to the Sass variables or maps, you’ll need to save your changes and recompile. Doing so will output a brand new set of predefined grid classes for column widths, offsets, and ordering. Responsive visibility utilities will also be updated to use the custom breakpoints. Make sure to set grid values in px (not rem, em, or %).