Customize the native <select>s with custom CSS that changes the element’s initial appearance.

Default

Custom <select> menus need only a custom class, .form-select to trigger the custom styles. Custom styles are limited to the <select>’s initial appearance and cannot modify the <option>s due to browser limitations.

<select class="form-select" aria-label="Default select example">
  <option selected>Open this select menu</option>
  <option value="1">One</option>
  <option value="2">Two</option>
  <option value="3">Three</option>
</select>

Sizing

You may also use large custom selects to match our similarly sized text inputs.

<select class="form-select form-select-lg mb-3" aria-label=".form-select-lg example">
  <option selected>Open this select menu</option>
  <option value="1">One</option>
  <option value="2">Two</option>
  <option value="3">Three</option>
</select>

The multiple attribute is also supported:

<select class="form-select" multiple aria-label="multiple select example">
  <option selected>Open this select menu</option>
  <option value="1">One</option>
  <option value="2">Two</option>
  <option value="3">Three</option>
</select>

As is the size attribute:

<select class="form-select" size="3" aria-label="size 3 select example">
  <option selected>Open this select menu</option>
  <option value="1">One</option>
  <option value="2">Two</option>
  <option value="3">Three</option>
</select>

Disabled

Add the disabled boolean attribute on a select to give it a grayed out appearance and remove pointer events.

<select class="form-select" aria-label="Disabled select example" disabled>
  <option selected>Open this select menu</option>
  <option value="1">One</option>
  <option value="2">Two</option>
  <option value="3">Three</option>
</select>

Sass

Variables

$form-select-padding-y:             $input-padding-y;
$form-select-padding-x:             $input-padding-x;
$form-select-font-family:           $input-font-family;
$form-select-font-size:             $input-font-size;
$form-select-indicator-padding:     $form-select-padding-x * 3; // Extra padding for background-image
$form-select-font-weight:           $input-font-weight;
$form-select-line-height:           $input-line-height;
$form-select-color:                 $input-color;
$form-select-bg:                    $input-bg;
$form-select-disabled-color:        $gray-700;
$form-select-disabled-bg:           $gray-300;
$form-select-disabled-border-color: $input-disabled-border-color;
$form-select-bg-position:           right $form-select-padding-x top add(50%, 1px);
$form-select-bg-size:               .875rem 1rem; // In pixels because image dimensions
$form-select-indicator:             url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 14 7'><path d='M7 7L0 0h14L7 7z'/></svg>");
$form-select-disabled-indicator:    url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 14 7'><path fill='#{$form-select-disabled-color}' d='M7 7L0 0h14L7 7z'/></svg>"); // Boosted mod

// Boosted mod: no icon for validated select

$form-select-border-width:        $input-border-width;
$form-select-border-color:        $input-border-color;
$form-select-border-radius:       $border-radius;
$form-select-box-shadow:          $box-shadow-inset;

$form-select-focus-border-color:  $input-focus-border-color;
$form-select-focus-box-shadow:    null;

// Boosted mod: no .form-select-sm

$form-select-padding-y-lg:        $spacer / 2;
$form-select-padding-x-lg:        $input-padding-x-lg;
$form-select-font-size-lg:        $input-font-size-lg;