Breakpoints

Breakpoints are the triggers in this framework for how your layout responsive changes across device or viewport sizes.

Core concepts

  • Breakpoints are the building blocks of responsive design. Use them to control when your layout can be adapted at a particular viewport or device size.
  • Use media queries to architect your CSS by breakpoint. Media queries are a feature of CSS that allow you to conditionally apply styles based on a set of browser and operating system parameters. We most commonly use min-width in our media queries.
  • Mobile first, responsive design is the goal. Bootstrap’s CSS aims to apply the bare minimum of styles to make a layout work at the smallest breakpoint, and then layers on styles to adjust that design for larger devices. This optimizes your CSS, improves rendering time, and provides a great experience for your visitors.

Available breakpoints

This framework includes six default breakpoints, sometimes referred to as grid tiers, for building responsively. These breakpoints can be customized if you’re using our source Sass files.

Breakpoint Class infix Dimentions
X-small None <576x< /td>
Small sm ≥576px
Medium md ≥768px
Large lg ≥992px
Extra large xl <576x< /td>
Extra extra large xxl ≥1400px
Each breakpoint was chosen to comfortably hold containers whose widths are multiples of 12. Breakpoints are also representative of a subset of common device sizes and viewport dimensions—they don’t specifically target every use case or device. Instead, the ranges provide a strong and consistent foundation to build on for nearly any device.

Media queries

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.

Min-width

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

// X-Small devices (portrait phones, less than 576px)
// No media query for `xs` 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) { ... }
 
// X-Large devices (large desktops, 1200px and up)
@media (min-width: 1200px) { ... }
 
// XX-Large devices (larger desktops, 1400px and up)
@media (min-width: 1400px) { ... }

Max-width

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

These mixins take those declared breakpoints, subtract .02px from them, and use them as our max-width values. For example:

// X-Small devices (portrait phones, less than 576px))
@media (max-width: 575.98px) { ... }
 
// Small devices (landscape phones, less than 768px)
@media (max-width: 767.98px) { ... }
 
// Medium devices (tablets, less than 992px)
@media (max-width: 991.98px) { ... }
 
// Large devices (desktops, less than 1200px)
@media (max-width: 1199.98px)) { ... }
 
// X-Large devices (large desktops, less than 1400px)
@media (max-width: 1399.98px) { ... } { ... }
 
// XX-Large devices (larger desktops)
// No media query since the xxl breakpoint has no upper bound on its width