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Dropdowns
Toggle contextual overlays for displaying lists of links and more with the Bootstrap dropdown plugin.
components
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Overview

Dropdowns are toggleable, contextual overlays for displaying lists of links and more. They're made interactive with the included Bootstrap dropdown JavaScript plugin. They're toggled by clicking, not by hovering; this is an intentional design decision.

Dropdowns are built on a third party library, Popper, which provides dynamic positioning and viewport detection. Be sure to include [popper.min.js]({{< param "cdn.popper" >}}) before Bootstrap's JavaScript or use bootstrap.bundle.min.js / bootstrap.bundle.js which contains Popper. Popper isn't used to position dropdowns in navbars though as dynamic positioning isn't required.

Accessibility

The WAI ARIA standard defines an actual role="menu" widget, but this is specific to application-like menus which trigger actions or functions. ARIA menus can only contain menu items, checkbox menu items, radio button menu items, radio button groups, and sub-menus.

Bootstrap's dropdowns, on the other hand, are designed to be generic and applicable to a variety of situations and markup structures. For instance, it is possible to create dropdowns that contain additional inputs and form controls, such as search fields or login forms. For this reason, Bootstrap does not expect (nor automatically add) any of the role and aria- attributes required for true ARIA menus. Authors will have to include these more specific attributes themselves.

However, Bootstrap does add built-in support for most standard keyboard menu interactions, such as the ability to move through individual .dropdown-item elements using the cursor keys and close the menu with the ESC key.

Examples

Wrap the dropdown's toggle (your button or link) and the dropdown menu within .dropdown, or another element that declares position: relative;. Dropdowns can be triggered from <a> or <button> elements to better fit your potential needs. The examples shown here use semantic <ul> elements where appropriate, but custom markup is supported.

Single button

Any single .btn can be turned into a dropdown toggle with some markup changes. Here's how you can put them to work with either <button> elements:

{{< example >}}

{{< /example >}}

And with <a> elements:

{{< example >}}

{{< /example >}}

The best part is you can do this with any button variant, too:

<!-- Example single danger button -->
<div class="btn-group">
  <button type="button" class="btn btn-danger dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Action
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Another action</a></li>
    <li><a class="dropdown-item" href="#">Something else here</a></li>
    <li><hr class="dropdown-divider"></li>
    <li><a class="dropdown-item" href="#">Separated link</a></li>
  </ul>
</div>

Split button

Similarly, create split button dropdowns with virtually the same markup as single button dropdowns, but with the addition of .dropdown-toggle-split for proper spacing around the dropdown caret.

We use this extra class to reduce the horizontal padding on either side of the caret by 25% and remove the margin-left that's added for regular button dropdowns. Those extra changes keep the caret centered in the split button and provide a more appropriately sized hit area next to the main button.

<!-- Example split danger button -->
<div class="btn-group">
  <button type="button" class="btn btn-danger">Action</button>
  <button type="button" class="btn btn-danger dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Another action</a></li>
    <li><a class="dropdown-item" href="#">Something else here</a></li>
    <li><hr class="dropdown-divider"></li>
    <li><a class="dropdown-item" href="#">Separated link</a></li>
  </ul>
</div>

Sizing

Button dropdowns work with buttons of all sizes, including default and split dropdown buttons.

<!-- Large button groups (default and split) -->
<div class="btn-group">
  <button class="btn btn-secondary btn-lg dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Large button
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>
<div class="btn-group">
  <button class="btn btn-secondary btn-lg" type="button">
    Large split button
  </button>
  <button type="button" class="btn btn-lg btn-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>
<div class="btn-group">
  <button class="btn btn-secondary btn-sm dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Small button
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>
<div class="btn-group">
  <button class="btn btn-secondary btn-sm" type="button">
    Small split button
  </button>
  <button type="button" class="btn btn-sm btn-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>

Dark dropdowns

Opt into darker dropdowns to match a dark navbar or custom style by adding .dropdown-menu-dark onto an existing .dropdown-menu. No changes are required to the dropdown items.

{{< example >}}

{{< /example >}}

And putting it to use in a navbar:

{{< example >}}

{{< /example >}}

Directions

{{< callout info >}}

RTL

Directions are mirrored when using Bootstrap in RTL, meaning .dropstart will appear on the right side. {{< /callout >}}

Centered

Make the dropdown menu centered below the toggle with .dropdown-center on the parent element.

{{< example >}}

Centered dropdown
{{< /example >}}

Dropup

Trigger dropdown menus above elements by adding .dropup to the parent element.

<!-- Default dropup button -->
<div class="btn-group dropup">
  <button type="button" class="btn btn-secondary dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropup
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

<!-- Split dropup button -->
<div class="btn-group dropup">
  <button type="button" class="btn btn-secondary">
    Split dropup
  </button>
  <button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

Dropup centered

Make the dropup menu centered above the toggle with .dropup-center on the parent element.

{{< example >}}

Centered dropup
{{< /example >}}

Dropend

Trigger dropdown menus at the right of the elements by adding .dropend to the parent element.

<!-- Default dropend button -->
<div class="btn-group dropend">
  <button type="button" class="btn btn-secondary dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropend
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

<!-- Split dropend button -->
<div class="btn-group dropend">
  <button type="button" class="btn btn-secondary">
    Split dropend
  </button>
  <button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropend</span>
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

Dropstart

Trigger dropdown menus at the left of the elements by adding .dropstart to the parent element.

<!-- Default dropstart button -->
<div class="btn-group dropstart">
  <button type="button" class="btn btn-secondary dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropstart
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

<!-- Split dropstart button -->
<div class="btn-group dropstart">
  <button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropstart</span>
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
  <button type="button" class="btn btn-secondary">
    Split dropstart
  </button>
</div>

Menu items

You can use <a> or <button> elements as dropdown items.

{{< example >}}

Dropdown
  • Action
  • Another action
  • Something else here
{{< /example >}}

You can also create non-interactive dropdown items with .dropdown-item-text. Feel free to style further with custom CSS or text utilities.

{{< example >}}

{{< /example >}}

Active

Add .active to items in the dropdown to style them as active. To convey the active state to assistive technologies, use the aria-current attribute — using the page value for the current page, or true for the current item in a set.

{{< example >}}

{{< /example >}}

Disabled

Add .disabled to items in the dropdown to style them as disabled.

{{< example >}}

{{< /example >}}

Menu alignment

By default, a dropdown menu is automatically positioned 100% from the top and along the left side of its parent. You can change this with the directional .drop* classes, but you can also control them with additional modifier classes.

Add .dropdown-menu-end to a .dropdown-menu to right align the dropdown menu. Directions are mirrored when using Bootstrap in RTL, meaning .dropdown-menu-end will appear on the left side.

{{< callout info >}} Heads up! Dropdowns are positioned thanks to Popper except when they are contained in a navbar. {{< /callout >}}

{{< example >}}

Right-aligned menu example
  • Action
  • Another action
  • Something else here
{{< /example >}}

Responsive alignment

If you want to use responsive alignment, disable dynamic positioning by adding the data-bs-display="static" attribute and use the responsive variation classes.

To align right the dropdown menu with the given breakpoint or larger, add .dropdown-menu{-sm|-md|-lg|-xl|-xxl}-end.

{{< example >}}

Left-aligned but right aligned when large screen
  • Action
  • Another action
  • Something else here
{{< /example >}}

To align left the dropdown menu with the given breakpoint or larger, add .dropdown-menu-end and .dropdown-menu{-sm|-md|-lg|-xl|-xxl}-start.

{{< example >}}

Right-aligned but left aligned when large screen
  • Action
  • Another action
  • Something else here
{{< /example >}}

Note that you don't need to add a data-bs-display="static" attribute to dropdown buttons in navbars, since Popper isn't used in navbars.

Alignment options

Taking most of the options shown above, here's a small kitchen sink demo of various dropdown alignment options in one place.

{{< example >}}

Right-aligned menu
Left-aligned, right-aligned lg
Right-aligned, left-aligned lg
{{< /example >}}

Menu content

Headers

Add a header to label sections of actions in any dropdown menu.

{{< example >}}

{{< /example >}}

Dividers

Separate groups of related menu items with a divider.

{{< example >}}

{{< /example >}}

Text

Place any freeform text within a dropdown menu with text and use [spacing utilities]({{< docsref "/utilities/spacing" >}}). Note that you'll likely need additional sizing styles to constrain the menu width.

{{< example >}}

Some example text that's free-flowing within the dropdown menu.

And this is more example text.

{{< /example >}}

Forms

Put a form within a dropdown menu, or make it into a dropdown menu, and use [margin or padding utilities]({{< docsref "/utilities/spacing" >}}) to give it the negative space you require.

{{< example >}}

Email address
Password
Remember me
Sign in
New around here? Sign up Forgot password?
{{< /example >}}

{{< example >}}

Dropdown form
Email address
Password
Remember me
Sign in
{{< /example >}}

Dropdown options

Use data-bs-offset or data-bs-reference to change the location of the dropdown.

{{< example >}}

{{< /example >}}

Auto close behavior

By default, the dropdown menu is closed when clicking inside or outside the dropdown menu. You can use the autoClose option to change this behavior of the dropdown.

{{< example >}}

Default dropdown
Clickable outside
Clickable inside
{{< /example >}}

CSS

Variables

{{< added-in "5.2.0" >}}

As part of Bootstrap's evolving CSS variables approach, dropdowns now use local CSS variables on .dropdown-menu for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.

{{< scss-docs name="dropdown-css-vars" file="scss/_dropdown.scss" >}}

Customization through CSS variables can be seen on the .dropdown-menu-dark class where we override specific values without adding duplicate CSS selectors.

{{< scss-docs name="dropdown-dark-css-vars" file="scss/_dropdown.scss" >}}

Sass variables

Variables for all dropdowns:

{{< scss-docs name="dropdown-variables" file="scss/_variables.scss" >}}

Variables for the dark dropdown:

{{< scss-docs name="dropdown-dark-variables" file="scss/_variables.scss" >}}

Variables for the CSS-based carets that indicate a dropdown's interactivity:

{{< scss-docs name="caret-variables" file="scss/_variables.scss" >}}

Mixins

Mixins are used to generate the CSS-based carets and can be found in scss/mixins/_caret.scss.

{{< scss-docs name="caret-mixins" file="scss/mixins/_caret.scss" >}}

Usage

Via data attributes or JavaScript, the dropdown plugin toggles hidden content (dropdown menus) by toggling the .show class on the parent .dropdown-menu. The data-bs-toggle="dropdown" attribute is relied on for closing dropdown menus at an application level, so it's a good idea to always use it.

{{< callout info >}} On touch-enabled devices, opening a dropdown adds empty mouseover handlers to the immediate children of the <body> element. This admittedly ugly hack is necessary to work around a quirk in iOS' event delegation, which would otherwise prevent a tap anywhere outside of the dropdown from triggering the code that closes the dropdown. Once the dropdown is closed, these additional empty mouseover handlers are removed. {{< /callout >}}

Via data attributes

Add data-bs-toggle="dropdown" to a link or button to toggle a dropdown.

<div class="dropdown">
  <button id="dLabel" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Dropdown trigger
  </button>
  <ul class="dropdown-menu" aria-labelledby="dLabel">
    ...
  </ul>
</div>

Via JavaScript

Call the dropdowns via JavaScript:

const dropdownElementList = document.querySelectorAll('.dropdown-toggle')
const dropdownList = [...dropdownElementList].map(dropdownToggleEl => new bootstrap.Dropdown(dropdownToggleEl))

{{< callout info >}}

data-bs-toggle="dropdown" still required

Regardless of whether you call your dropdown via JavaScript or instead use the data-api, data-bs-toggle="dropdown" is always required to be present on the dropdown's trigger element. {{< /callout >}}

Options

{{< markdown >}} {{< partial "js-data-attributes.md" >}} {{< /markdown >}}

{{< bs-table "table" >}}

Name Type Default Description
autoClose boolean, string true Configure the auto close behavior of the dropdown:
  • true - the dropdown will be closed by clicking outside or inside the dropdown menu.
  • false - the dropdown will be closed by clicking the toggle button and manually calling hide or toggle method. (Also will not be closed by pressing esc key)
  • 'inside' - the dropdown will be closed (only) by clicking inside the dropdown menu.
  • 'outside' - the dropdown will be closed (only) by clicking outside the dropdown menu.
Note: the dropdown can always be closed with the ESC key
boundary string, element 'scrollParent' Overflow constraint boundary of the dropdown menu (applies only to Popper's preventOverflow modifier). By default it's clippingParents and can accept an HTMLElement reference (via JavaScript only). For more information refer to Popper's detectOverflow docs.
display string 'dynamic' By default, we use Popper for dynamic positioning. Disable this with static.
offset number, string, function [0, 2] Offset of the dropdown relative to its target. You can pass a string in data attributes with comma separated values like: data-bs-offset="10,20". When a function is used to determine the offset, it is called with an object containing the popper placement, the reference, and popper rects as its first argument. The triggering element DOM node is passed as the second argument. The function must return an array with two numbers: skidding, distance. For more information refer to Popper's offset docs.
popperConfig null, object, function null To change Bootstrap's default Popper config, see Popper's configuration. When a function is used to create the Popper configuration, it's called with an object that contains the Bootstrap's default Popper configuration. It helps you use and merge the default with your own configuration. The function must return a configuration object for Popper.
reference string, element 'toggle' Reference element of the dropdown menu. Accepts the values of 'toggle', 'parent', an HTMLElement reference or an object providing getBoundingClientRect. For more information refer to Popper's constructor docs and virtual element docs.
{{< /bs-table >}}

Using function with popperConfig

const dropdown = new bootstrap.Dropdown(element, {
  popperConfig(defaultBsPopperConfig) {
    // const newPopperConfig = {...}
    // use defaultBsPopperConfig if needed...
    // return newPopperConfig
  }
})

Methods

{{< bs-table >}}

Method Description
dispose Destroys an element's dropdown. (Removes stored data on the DOM element)
getInstance Static method which allows you to get the dropdown instance associated to a DOM element, you can use it like this: bootstrap.Dropdown.getInstance(element)
getOrCreateInstance Static method which returns a dropdown instance associated to a DOM element or create a new one in case it wasn't initialized. You can use it like this: bootstrap.Dropdown.getOrCreateInstance(element).
hide Hides the dropdown menu of a given navbar or tabbed navigation.
show Shows the dropdown menu of a given navbar or tabbed navigation.
toggle Toggles the dropdown menu of a given navbar or tabbed navigation.
update Updates the position of an element's dropdown.
{{< /bs-table >}}

Events

All dropdown events are fired at the toggling element and then bubbled up. So you can also add event listeners on the .dropdown-menu's parent element. hide.bs.dropdown and hidden.bs.dropdown events have a clickEvent property (only when the original Event type is click) that contains an Event Object for the click event.

{{< bs-table >}}

Event type Description
hide.bs.dropdown Fires immediately when the hide instance method has been called.
hidden.bs.dropdown Fired when the dropdown has finished being hidden from the user and CSS transitions have completed.
show.bs.dropdown Fires immediately when the show instance method is called.
shown.bs.dropdown Fired when the dropdown has been made visible to the user and CSS transitions have completed.
{{< /bs-table >}} 
const myDropdown = document.getElementById('myDropdown')
myDropdown.addEventListener('show.bs.dropdown', event => {
  // do something...
})