Grid system

How it works

Breaking it down, here’s how the grid system comes together:

Our grid supports six responsive breakpoints. Breakpoints are based on min-width media queries, meaning they affect that breakpoint and all those above it (e.g., .col-sm-4 applies to sm, md, lg, xl, and xxl). This means you can control container and column sizing and behavior by each breakpoint.
Containers center and horizontally pad your content. Use .container for a responsive pixel width, .container-fluid for width: 100% across all viewports and devices, or a responsive container (e.g., .container-md) for a combination of fluid and pixel widths.
Rows are wrappers for columns. Each column has horizontal padding (called a gutter) for controlling the space between them. This padding is then counteracted on the rows with negative margins to ensure the content in your columns is visually aligned down the left side. Rows also support modifier classes to uniformly apply column sizing and gutter classes to change the spacing of your content.
Columns are incredibly flexible. There are 12 template columns available per row, allowing you to create different combinations of elements that span any number of columns. Column classes indicate the number of template columns to span (e.g., col-4 spans four). widths are set in percentages so you always have the same relative sizing.

Grid options

Grid system can adapt across all six default breakpoints, and any breakpoints you customize. The six default grid tiers are as follow:

Extra small (xs)
Small (sm)
Medium (md)
Large (lg)
Extra large (xl)
Extra extra large (xxl)

As noted above, each of these breakpoints have their own container, unique class prefix, and modifiers. Here’s how the grid changes across these breakpoints:

	xs <576px	sm ≥576px	md ≥768px	lg ≥992px	xl ≥1200px	xxl ≥1400px
Container `max-width`	None (auto)	540px	720px	960px	1140px	1320px
Class prefix	`.col-`	`.col-sm-`	`.col-md-`	`.col-lg-`	`.col-xl-`	`.col-xxl-`
of columns	12

Equal-width

For example, here are two grid layouts that apply to every device and viewport, from xs to xxl. 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 text-center">
  <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>

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 text-center">
	<div class="row">
	  <div class="col"> 1 of 3 </div>
	  <div class="col-6"> 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-5"> 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 text-center">
	<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>

Responsive classes

grid includes six 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.

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-8

col-4

<div class="container text-center">
	<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-8">col-8</div>
	  <div class="col-4">col-4</div>
	</div>
  </div>

Stacked to horizontal

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

col-sm-8

col-sm-4

col-sm

<div class="container text-center">
	<div class="row">
	  <div class="col-sm-8">col-sm-8</div>
	  <div class="col-sm-4">col-sm-4</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>
  </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-md-8

.col-6 .col-md-4

.col-6

<div class="container text-center">
	<!-- Stack the columns on mobile by making one full-width and the other half-width -->
	<div class="row">
	  <div class="col-md-8">.col-md-8</div>
	  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
	</div>
  
	<!-- Columns start at 50% wide on mobile and bump up to 33.3% wide on desktop -->
	<div class="row">
	  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
	  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
	  <div class="col-6 col-md-4">.col-6 .col-md-4</div>
	</div>
  
	<!-- Columns are always 50% wide, on mobile and desktop -->
	<div class="row">
	  <div class="col-6">.col-6</div>
	  <div class="col-6">.col-6</div>
	</div>
  </div>

Row columns

Use the responsive .row-cols-* classes to quickly set the number of columns that best render your content and layout. Whereas normal .col-* classes apply to the individual columns (e.g., .col-md-4), the row columns classes are set on the parent .row as a shortcut. With .row-cols-auto you can give the columns their natural width.

Use these row columns classes to quickly create basic grid layouts or to control your card layouts.

Column

<div class="container text-center">
	<div class="row row-cols-2">
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
    </div>
</div>

Column

<div class="container text-center">
    <div class="row row-cols-3">
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
    </div>
</div>

Column

<div class="container text-center">
	<div class="row row-cols-auto">
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
    </div>
</div>

Column

<div class="container text-center">
	<div class="row row-cols-4">
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
	    <div class="col">Column</div>
    </div>
</div>

Column

<div class="container text-center">
	<div class="row row-cols-2">
		<div class="col">Column</div>
		<div class="col">Column</div>
		<div class="col-6">Column</div>
		<div class="col">Column</div>
	</div>
</div>

Column

<div class="container text-center">
	<div class="row row-cols-1 row-cols-sm-2 row-cols-md-4">
		 <div class="col">Column</div>
		 <div class="col">Column</div>
		 <div class="col">Column</div>
		 <div class="col">Column</div>
	</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-3

Level 2: .col-8 .col-sm-6

Level 2: .col-4 .col-sm-6

<div class="container text-center">
	<div class="row">
	     <div class="col-sm-3"> Level 1: .col-sm-3 </div>
	     <div class="col-sm-9">
	        <div class="row">
		        <div class="col-8 col-sm-6"> Level 2: .col-8 .col-sm-6 </div>
		        <div class="col-4 col-sm-6"> Level 2: .col-4 .col-sm-6 </div>
	        </div>
	    </div>
	</div>
</div>