Grid system
Use our powerful mobile-first flexbox grid to build layouts of all shapes and sizes thanks to a twelve column system, five default responsive tiers, Sass variables and mixins, and dozens of predefined classes.
Example
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.
<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>
Grid options
While Bootstrap uses em
s or rem
s for defining most sizes, px
s 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.
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
.
<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.
<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>
Media object
Documentation and examples for Bootstrap’s media object to construct highly repetitive components like blog comments, tweets, and the like.
Example
The media object helps build complex and repetitive components where some media is positioned alongside content that doesn’t wrap around said media. Plus, it does this with only two required classes thanks to flexbox.
Media heading
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
<div class="media">
<img class="mr-3" src="..." alt="Generic placeholder image">
<div class="media-body">
<h5 class="mt-0">Media heading</h5>
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
</div>
</div>
Nesting
Media objects can be infinitely nested, though we suggest you stop at some point. Place nested .media within the .media-body of a parent media object.
Media heading
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
<div class="media">
<img class="mr-3" src="..." alt="Generic placeholder image">
<div class="media-body">
<h5 class="mt-0">Media heading</h5>
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
<div class="media mt-3">
<a class="pr-3" href="#">
<img src="..." alt="Generic placeholder image">
</a>
<div class="media-body">
<h5 class="mt-0">Media heading</h5>
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
</div>
</div>
</div>
</div>
Alignment
Media in a media object can be aligned with flexbox utilities to the top (default), middle, or end of your .media-body content.
Top-aligned media
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
Donec sed odio dui. Nullam quis risus eget urna mollis ornare vel eu leo. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.
<div class="media">
<img class="align-self-start mr-3" src="..." alt="Generic placeholder image">
<div class="media-body">
<h5 class="mt-0">Top-aligned media</h5>
<p>Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.</p>
<p>Donec sed odio dui. Nullam quis risus eget urna mollis ornare vel eu leo. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.</p>
</div>
</div>
Utilities for layout
For faster mobile-friendly and responsive development, Bootstrap includes dozens of utility classes for showing, hiding, aligning, and spacing content.
Changing display
Use our display utilities for responsively toggling common values of the display
property. Mix it with our grid system, content, or components to show or hide them across specific viewports.
Flexbox options
Bootstrap 4 is built with flexbox, but not every element’s display
has been changed to display: flex
as this would add many unnecessary overrides and unexpectedly change key browser behaviors. Most of our components are built with flexbox enabled.
Margin and padding
Use the margin
and padding
spacing utilities to control how elements and components are spaced and sized. Bootstrap 4 includes a five-level scale for spacing utilities, based on a 1rem
value default $spacer
variable. Choose values for all viewports (e.g., .mr-3
for margin-right: 1rem
), or pick responsive variants to target specific viewports (e.g., .mr-md-3
for margin-right: 1rem
starting at the md
breakpoint).
Toggle visibility
When toggling display
isn’t needed, you can toggle the visibility
of an element with our visibility utilities. Invisible elements will still affect the layout of the page, but are visually hidden from visitors.