Carousel

How it works

• The carousel is a slideshow for cycling through a series of content, built with CSS 3D transforms and a bit of JavaScript. It works with a series of images, text, or custom markup. It also includes support for previous/next controls and indicators.

• For performance reasons, carousels must be manually initialized using the carousel constructor method. Without initialization, some of the event listeners (specifically, the events needed touch/swipe support) will not be registered until a user has explicitly activated a control or indicator.

  The only exception are autoplaying carousels with the data-bs-ride="carousel" attribute as these are initialized automatically on page load. If you’re using autoplaying carousels with the data attribute, don’t explicitly initialize the same carousels with the constructor method.

• Nested carousels are not supported. You should also be aware that carousels in general can often cause usability and accessibility challenges.

Basic examples

Here is a basic example of a carousel with three slides. Note the previous/next controls. We recommend using <button> elements, but you can also use <a> elements with role="button".

Carousels don’t automatically normalize slide dimensions. As such, you may need to use additional utilities or custom styles to appropriately size content. While carousels support previous/next controls and indicators, they’re not explicitly required. Add and customize as you see fit.

You must add the .active class to one of the slides, otherwise the carousel will not be visible. Also be sure to set a unique id on the .carousel for optional controls, especially if you’re using multiple carousels on a single page. Control and indicator elements must have a data-bs-target attribute (or href for links) that matches the id of the .carousel element.

Indicators

You can add indicators to the carousel, alongside the previous/next controls. The indicators let users jump directly to a particular slide.

Captions

You can add captions to your slides with the .carousel-caption element within any .carousel-item. They can be easily hidden on smaller viewports, as shown below, with optional display utilities. We hide them initially with .d-none and bring them back on medium-sized devices with .d-md-block.

Crossfade

Add .carousel-fade to your carousel to animate slides with a fade transition instead of a slide. Depending on your carousel content (e.g., text only slides), you may want to add .bg-body or some custom CSS to the .carousel-items for proper crossfading.

Autoplaying carousels

You can make your carousels autoplay on page load by setting the ride option to carousel. Autoplaying carousels automatically pause while hovered with the mouse. This behavior can be controlled with the pause option. In browsers that support the Page Visibility API, the carousel will stop cycling when the webpage is not visible to the user (such as when the browser tab is inactive, or when the browser window is minimized).

When the ride option is set to true, rather than carousel, the carousel won’t automatically start to cycle on page load. Instead, it will only start after the first user interaction.

Individual .carousel-item interval

Add data-bs-interval="" to a .carousel-item to change the amount of time to delay between automatically cycling to the next item.

Autoplaying carousels without controls

Here’s a carousel with slides only. Note the presence of the .d-block and .w-100 on carousel images to prevent browser default image alignment.

Disable touch swiping

Carousels support swiping left/right on touchscreen devices to move between slides. This can be disabled by setting the touch option to false.

Dark variant

Add .carousel-dark to the .carousel for darker controls, indicators, and captions. Controls are inverted compared to their default white fill with the filter CSS property. Captions and controls have additional Sass variables that customize the color and background-color.

Custom transition

The transition duration of .carousel-item can be changed with the $carousel-transition-duration Sass variable before compiling or custom styles if you’re using the compiled CSS. If multiple transitions are applied, make sure the transform transition is defined first (e.g. transition: transform 2s ease, opacity .5s ease-out).

CSS

Sass variables

Variables for all carousels:

$carousel-control-color:             $white;
$carousel-control-width:             15%;
$carousel-control-opacity:           .5;
$carousel-control-hover-opacity:     .9;
$carousel-control-transition:        opacity .15s ease;

$carousel-indicator-width:           30px;
$carousel-indicator-height:          3px;
$carousel-indicator-hit-area-height: 10px;
$carousel-indicator-spacer:          3px;
$carousel-indicator-opacity:         .5;
$carousel-indicator-active-bg:       $white;
$carousel-indicator-active-opacity:  1;
$carousel-indicator-transition:      opacity .6s ease;

$carousel-caption-width:             70%;
$carousel-caption-color:             $white;
$carousel-caption-padding-y:         1.25rem;
$carousel-caption-spacer:            1.25rem;

$carousel-control-icon-width:        2rem;

$carousel-control-prev-icon-bg:      url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='#{$carousel-control-color}'><path d='M11.354 1.646a.5.5 0 0 1 0 .708L5.707 8l5.647 5.646a.5.5 0 0 1-.708.708l-6-6a.5.5 0 0 1 0-.708l6-6a.5.5 0 0 1 .708 0z'/></svg>");
$carousel-control-next-icon-bg:      url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='#{$carousel-control-color}'><path d='M4.646 1.646a.5.5 0 0 1 .708 0l6 6a.5.5 0 0 1 0 .708l-6 6a.5.5 0 0 1-.708-.708L10.293 8 4.646 2.354a.5.5 0 0 1 0-.708z'/></svg>");

$carousel-transition-duration:       .6s;
$carousel-transition:                transform $carousel-transition-duration ease-in-out; // Define transform transition first if using multiple transitions (e.g., `transform 2s ease, opacity .5s ease-out`)

Variables for the dark carousel:

$carousel-dark-indicator-active-bg:  $black;
$carousel-dark-caption-color:        $black;
$carousel-dark-control-icon-filter:  invert(1) grayscale(100);

Usage

Via data attributes

Use data attributes to easily control the position of the carousel. data-bs-slide accepts the keywords prev or next, which alters the slide position relative to its current position. Alternatively, use data-bs-slide-to to pass a raw slide index to the carousel data-bs-slide-to="2", which shifts the slide position to a particular index beginning with 0.

Via JavaScript

Call carousel manually with:

const carousel = new bootstrap.Carousel('#myCarousel')

Options

As options can be passed via data attributes or JavaScript, you can append an option name to data-bs-, as in data-bs-animation="{value}". Make sure to change the case type of the option name from “camelCase” to “kebab-case” when passing the options via data attributes. For example, use data-bs-custom-class="beautifier" instead of data-bs-customClass="beautifier".

As of Bootstrap 5.2.0, all components support an experimental reserved data attribute data-bs-config that can house simple component configuration as a JSON string. When an element has data-bs-config='{"delay":0, "title":123}' and data-bs-title="456" attributes, the final title value will be 456 and the separate data attributes will override values given on data-bs-config. In addition, existing data attributes are able to house JSON values like data-bs-delay='{"show":0,"hide":150}'.

Methods

You can create a carousel instance with the carousel constructor, and pass on any additional options. For example, to manually initialize an autoplaying carousel (assuming you’re not using the data-bs-ride="carousel" attribute in the markup itself) with a specific interval and with touch support disabled, you can use:

const myCarouselElement = document.querySelector('#myCarousel')

const carousel = new bootstrap.Carousel(myCarouselElement, {
  interval: 2000,
  touch: false
})

Events

Bootstrap’s carousel class exposes two events for hooking into carousel functionality. Both events have the following additional properties:

• direction: The direction in which the carousel is sliding (either "left" or "right").
• relatedTarget: The DOM element that is being slid into place as the active item.
• from: The index of the current item
• to: The index of the next item

All carousel events are fired at the carousel itself (i.e. at the <div class="carousel">).

const myCarousel = document.getElementById('myCarousel')

myCarousel.addEventListener('slide.bs.carousel', event => {
  // do something...
})