Documentation v1.0.0

Z-index

---
title: Z-index
description: Use our low-level `z-index` utilities to quickly change the stack level of an element or component.
toc: true
---

## Example

Use `z-index` utilities to stack elements on top of one another. Requires a `position` value other than `static`, which can be set with custom styles or using our [position utilities](/docs/utilities/position/).

<Callout type="info">
  We call these “low-level” `z-index` utilities because of their default values of `-1` through `3`, which we use for
  the layout of overlapping components. High-level `z-index` values are used for overlay components like modals and
  tooltips.
</Callout>

## Overlays

Bootstrap overlay components—dropdown, modal, offcanvas, popover, toast, and tooltip—all have their own `z-index` values to ensure a usable experience with competing “layers” of an interface.

Read about them in the [`z-index` layout page](/docs/layout/z-index).

## Component approach

On some components, we use our low-level `z-index` values to manage repeating elements that overlap one another (like buttons in a button group or items in a list group).

Learn about our [`z-index` approach](/docs/extend/approach#z-index-scales).

Use our low-level `z-index` utilities to quickly change the stack level of an element or component.

Example

Use z-index utilities to stack elements on top of one another. Requires a position value other than static, which can be set with custom styles or using our position utilities.

We call these “low-level” z-index utilities because of their default values of -1 through 3, which we use for the layout of overlapping components. High-level z-index values are used for overlay components like modals and tooltips.

z-3

z-2

z-1

z-0

z-n1

<div class="z-3 position-absolute p-5 rounded-3"><span>z-3</span></div>
<div class="z-2 position-absolute p-5 rounded-3"><span>z-2</span></div>
<div class="z-1 position-absolute p-5 rounded-3"><span>z-1</span></div>
<div class="z-0 position-absolute p-5 rounded-3"><span>z-0</span></div>
<div class="z-n1 position-absolute p-5 rounded-3"><span>z-n1</span></div>

Overlays

Bootstrap overlay components—dropdown, modal, offcanvas, popover, toast, and tooltip—all have their own z-index values to ensure a usable experience with competing “layers” of an interface.

Read about them in the z-index layout page.

Component approach

On some components, we use our low-level z-index values to manage repeating elements that overlap one another (like buttons in a button group or items in a list group).

Learn about our z-index approach.

On this page