---
title: Borders
description: Use border utilities to quickly style the border and border-radius of an element. Great for images, buttons, or any other element.
toc: true
---

import { getData } from '@libs/data'

## Border

Use border utilities to add or remove an element’s borders. Choose from all borders or one at a time.

### Additive

Add borders to custom elements:

<Example class="bd-example-border-utils" code={`

`} />

### Subtractive

Or remove borders:

<Example class="bd-example-border-utils" code={`

`} />

## Color

<Callout>
Border utilities like `.border-*` that generated from our original `$theme-colors` Sass map don’t yet respond to color modes, however, any `.border-*-subtle` utility will. This will be resolved in v6.
</Callout>

Change the border color using utilities built on our theme colors.

<Example class="bd-example-border-utils" code={[
  ...getData('theme-colors').map((themeColor) => `
`),
  `
`
]} />

Or modify the default `border-color` of a component:

<Example code={`
    Email address

    Dangerous heading

    Changing border color and width
  
`} />

## Opacity

<AddedIn version="5.2.0" />

Bootstrap `border-{color}` utilities are generated with Sass using CSS variables. This allows for real-time color changes without compilation and dynamic alpha transparency changes.

### How it works

Consider our default `.border-success` utility.

```css
.border-success {
  --bs-border-opacity: 1;
  border-color: rgba(var(--bs-success-rgb), var(--bs-border-opacity)) !important;
}
```

We use an RGB version of our `--bs-success` (with the value of `25, 135, 84`) CSS variable and attached a second CSS variable, `--bs-border-opacity`, for the alpha transparency (with a default value `1` thanks to a local CSS variable). That means anytime you use `.border-success` now, your computed `color` value is `rgba(25, 135, 84, 1)`. The local CSS variable inside each `.border-*` class avoids inheritance issues so nested instances of the utilities don’t automatically have a modified alpha transparency.

### Example

To change that opacity, override `--bs-border-opacity` via custom styles or inline styles.

<Example code={`
This is default success border

This is 50% opacity success border
`} />

Or, choose from any of the `.border-opacity` utilities:

<Example code={`
This is default success border

This is 75% opacity success border

This is 50% opacity success border

This is 25% opacity success border

This is 10% opacity success border
`} />

## Width

<Example class="bd-example-border-utils" code={`

`} />

## Radius

Add classes to an element to easily round its corners.

<Example class="bd-example-rounded-utils" code={`<Placeholder width="75" height="75" class="rounded" title="Example rounded image" />
<Placeholder width="75" height="75" class="rounded-top" title="Example top rounded image" />
<Placeholder width="75" height="75" class="rounded-end" title="Example right rounded image" />
<Placeholder width="75" height="75" class="rounded-bottom" title="Example bottom rounded image" />
<Placeholder width="75" height="75" class="rounded-start" title="Example left rounded image" />`} />

### Sizes

Use the scaling classes for larger or smaller rounded corners. Sizes range from `0` to `5` including `circle` and `pill`, and can be configured by modifying the utilities API.

<Example class="bd-example-rounded-utils" code={`<Placeholder width="75" height="75" class="rounded-0" title="Example non-rounded image" />
<Placeholder width="75" height="75" class="rounded-1" title="Example small rounded image" />
<Placeholder width="75" height="75" class="rounded-2" title="Example default rounded image" />
<Placeholder width="75" height="75" class="rounded-3" title="Example large rounded image" />
<Placeholder width="75" height="75" class="rounded-4" title="Example larger rounded image" />
<Placeholder width="75" height="75" class="rounded-5" title="Example extra large rounded image" />
<Placeholder width="75" height="75" class="rounded-circle" title="Completely round image" />
<Placeholder width="150" height="75" class="rounded-pill" title="Rounded pill image" />`} />

<Example class="bd-example-rounded-utils" code={`<Placeholder width="75" height="75" class="rounded-bottom-1" title="Example small rounded image" />
<Placeholder width="75" height="75" class="rounded-start-2" title="Example default left rounded image" />
<Placeholder width="75" height="75" class="rounded-end-circle" title="Example right completely round image" />
<Placeholder width="75" height="75" class="rounded-start-pill" title="Example left rounded pill image" />
<Placeholder width="75" height="75" class="rounded-5 rounded-top-0" title="Example extra large bottom rounded image" />`} />

## CSS

### Variables

<AddedIn version="5.2.0" />

<ScssDocs name="root-border-var" file="scss/_root.scss" />

### Sass variables

<ScssDocs name="border-variables" file="scss/_variables.scss" />

<ScssDocs name="border-radius-variables" file="scss/_variables.scss" />

Variables for setting `border-color` in `.border-*-subtle` utilities in light and dark mode:

<ScssDocs name="theme-border-subtle-variables" file="scss/_variables.scss" />

<ScssDocs name="theme-border-subtle-dark-variables" file="scss/_variables-dark.scss" />

### Sass maps

Color mode adaptive border colors are also available as a Sass map:

<ScssDocs name="theme-border-subtle-map" file="scss/_maps.scss" />

<ScssDocs name="theme-border-subtle-dark-map" file="scss/_maps.scss" />

### Sass mixins

<ScssDocs name="border-radius-mixins" file="scss/mixins/_border-radius.scss" />

### Sass utilities API

Border utilities are declared in our utilities API in `scss/_utilities.scss`. [Learn how to use the utilities API.]([[docsref:/utilities/api#using-the-api]])

<ScssDocs name="utils-borders" file="scss/_utilities.scss" />

<ScssDocs name="utils-border-radius" file="scss/_utilities.scss" />
