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Bootstrap/site/content/docs/4.3/components/navbar.md
Martijn Cuppens 9daf36fdb7 Bootstrap 5 grid documentation
Co-authored-by: Mark Otto <markd.otto@gmail.com>
2020-03-10 20:30:29 +01:00

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Markdown

---
layout: docs
title: Navbar
description: Documentation and examples for Bootstrap's powerful, responsive navigation header, the navbar. Includes support for branding, navigation, and more, including support for our collapse plugin.
group: components
toc: true
---
## How it works
Here's what you need to know before getting started with the navbar:
- Navbars require a wrapping `.navbar` with `.navbar-expand{-sm|-md|-lg|-xl}` for responsive collapsing and [color scheme](#color-schemes) classes.
- Navbars and their contents are fluid by default. Change the [container](#containers) to limit their horizontal width in different ways.
- Use our [spacing]({{< docsref "/utilities/spacing" >}}) and [flex]({{< docsref "/utilities/flex" >}}) utility classes for controlling spacing and alignment within navbars.
- Navbars are responsive by default, but you can easily modify them to change that. Responsive behavior depends on our Collapse JavaScript plugin.
- Ensure accessibility by using a `<nav>` element or, if using a more generic element such as a `<div>`, add a `role="navigation"` to every navbar to explicitly identify it as a landmark region for users of assistive technologies.
- Indicate the current item by using `aria-current="page"` for the current page or `aria-current="true"` for the current item in a set.
{{< callout info >}}
{{< partial "callout-info-prefersreducedmotion.md" >}}
{{< /callout >}}
Read on for an example and list of supported sub-components.
## Supported content
Navbars come with built-in support for a handful of sub-components. Choose from the following as needed:
- `.navbar-brand` for your company, product, or project name.
- `.navbar-nav` for a full-height and lightweight navigation (including support for dropdowns).
- `.navbar-toggler` for use with our collapse plugin and other [navigation toggling](#responsive-behaviors) behaviors.
- Flex and spacing utilities for any form controls and actions.
- `.navbar-text` for adding vertically centered strings of text.
- `.collapse.navbar-collapse` for grouping and hiding navbar contents by a parent breakpoint.
Here's an example of all the sub-components included in a responsive light-themed navbar that automatically collapses at the `lg` (large) breakpoint.
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarSupportedContent">
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-expanded="false">
Dropdown
</a>
<ul class="dropdown-menu" aria-labelledby="navbarDropdown">
<li><a class="dropdown-item" href="#">Action</a></li>
<li><a class="dropdown-item" href="#">Another action</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#">Something else here</a></li>
</ul>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</li>
</ul>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success" type="submit">Search</button>
</form>
</div>
</div>
</nav>
{{< /example >}}
This example uses [color]({{< docsref "/utilities/colors" >}}) (`bg-light`) and [spacing]({{< docsref "/utilities/spacing" >}}) (`my-2`, `my-lg-0`, `mr-sm-0`, `my-sm-0`) utility classes.
### Brand
The `.navbar-brand` can be applied to most elements, but an anchor works best as some elements might require utility classes or custom styles.
{{< example >}}
<!-- As a link -->
<nav class="navbar navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
</div>
</nav>
<!-- As a heading -->
<nav class="navbar navbar-light bg-light">
<div class="container-fluid">
<span class="navbar-brand mb-0 h1">Navbar</span>
</div>
</nav>
{{< /example >}}
Adding images to the `.navbar-brand` will likely always require custom styles or utilities to properly size. Here are some examples to demonstrate.
{{< example >}}
<!-- Just an image -->
<nav class="navbar navbar-light bg-light">
<div class="container">
<a class="navbar-brand" href="#">
<img src="/docs/{{< param docs_version >}}/assets/brand/bootstrap-solid.svg" width="30" height="30" alt="" loading="lazy">
</a>
</div>
</nav>
{{< /example >}}
{{< example >}}
<!-- Image and text -->
<nav class="navbar navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">
<img src="/docs/{{< param docs_version >}}/assets/brand/bootstrap-solid.svg" width="30" height="30" class="d-inline-block align-top" alt="" loading="lazy">
Bootstrap
</a>
</div>
</nav>
{{< /example >}}
### Nav
Navbar navigation links build on our `.nav` options with their own modifier class and require the use of [toggler classes](#toggler) for proper responsive styling. **Navigation in navbars will also grow to occupy as much horizontal space as possible** to keep your navbar contents securely aligned.
Active states—with `.active`—to indicate the current page can be applied directly to `.nav-link`s or their immediate parent `.nav-item`s.
Please note that you should also add the `aria-current` attribute on the `.nav-link` itself.
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</li>
</ul>
</div>
</div>
</nav>
{{< /example >}}
And because we use classes for our navs, you can avoid the list-based approach entirely if you like.
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavAltMarkup" aria-controls="navbarNavAltMarkup" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNavAltMarkup">
<div class="navbar-nav">
<a class="nav-item nav-link active" aria-current="page" href="#">Home</a>
<a class="nav-item nav-link" href="#">Features</a>
<a class="nav-item nav-link" href="#">Pricing</a>
<a class="nav-item nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</div>
</div>
</div>
</nav>
{{< /example >}}
You may also utilize dropdowns in your navbar nav. Dropdown menus require a wrapping element for positioning, so be sure to use separate and nested elements for `.nav-item` and `.nav-link` as shown below.
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNavDropdown">
<ul class="navbar-nav">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="navbarDropdownMenuLink" role="button" data-toggle="dropdown" aria-expanded="false">
Dropdown link
</a>
<ul class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">
<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>
</ul>
</li>
</ul>
</div>
</div>
</nav>
{{< /example >}}
### Forms
Place various form controls and components within a navbar:
{{< example >}}
<nav class="navbar navbar-light bg-light">
<div class="container-fluid">
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success" type="submit">Search</button>
</form>
</div>
</nav>
{{< /example >}}
Immediate children elements in `.navbar` use flex layout and will default to `justify-content: space-between`. Use additional [flex utilities]({{< docsref "/utilities/flex" >}}) as needed to adjust this behavior.
{{< example >}}
<nav class="navbar navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand">Navbar</a>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success" type="submit">Search</button>
</form>
</div>
</nav>
{{< /example >}}
Input groups work, too. If your navbar is an entire form, or mostly form, you can use the `<form>` element as the container and save some HTML. Applies to the option above and below this copy.
{{< example >}}
<nav class="navbar navbar-light bg-light">
<form class="container-fluid">
<div class="input-group">
<div class="input-group-prepend">
<span class="input-group-text" id="basic-addon1">@</span>
</div>
<input type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="basic-addon1">
</div>
</form>
</nav>
{{< /example >}}
Various buttons are supported as part of these navbar forms, too. This is also a great reminder that vertical alignment utilities can be used to align different sized elements.
{{< example >}}
<nav class="navbar navbar-light bg-light">
<form class="container-fluid justify-content-start">
<button class="btn btn-outline-success mr-2" type="button">Main button</button>
<button class="btn btn-sm btn-outline-secondary" type="button">Smaller button</button>
</form>
</nav>
{{< /example >}}
### Text
Navbars may contain bits of text with the help of `.navbar-text`. This class adjusts vertical alignment and horizontal spacing for strings of text.
{{< example >}}
<nav class="navbar navbar-light bg-light">
<div class="container-fluid">
<span class="navbar-text">
Navbar text with an inline element
</span>
</div>
</nav>
{{< /example >}}
Mix and match with other components and utilities as needed.
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar w/ text</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarText" aria-controls="navbarText" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarText">
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
</ul>
<span class="navbar-text">
Navbar text with an inline element
</span>
</div>
</div>
</nav>
{{< /example >}}
## Color schemes
Theming the navbar has never been easier thanks to the combination of theming classes and `background-color` utilities. Choose from `.navbar-light` for use with light background colors, or `.navbar-dark` for dark background colors. Then, customize with `.bg-*` utilities.
<div class="bd-example">
<nav class="navbar navbar-expand-lg navbar-dark bg-dark">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarColor01" aria-controls="navbarColor01" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarColor01">
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">About</a>
</li>
</ul>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-info" type="submit">Search</button>
</form>
</div>
</div>
</nav>
<nav class="navbar navbar-expand-lg navbar-dark bg-primary">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarColor02" aria-controls="navbarColor02" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarColor02">
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">About</a>
</li>
</ul>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-light" type="submit">Search</button>
</form>
</div>
</div>
</nav>
<nav class="navbar navbar-expand-lg navbar-light" style="background-color: #e3f2fd;">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarColor03" aria-controls="navbarColor03" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarColor03">
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Features</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">About</a>
</li>
</ul>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-primary" type="submit">Search</button>
</form>
</div>
</div>
</nav>
</div>
{{< highlight html >}}
<nav class="navbar navbar-dark bg-dark">
<!-- Navbar content -->
</nav>
<nav class="navbar navbar-dark bg-primary">
<!-- Navbar content -->
</nav>
<nav class="navbar navbar-light" style="background-color: #e3f2fd;">
<!-- Navbar content -->
</nav>
{{< /highlight >}}
## Containers
Although it's not required, you can wrap a navbar in a `.container` to center it on a page or add one within to only center the contents of a [fixed or static top navbar](#placement). Note that an inner container is still required.
{{< example >}}
<div class="container">
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
</div>
</nav>
</div>
{{< /example >}}
Use any of the responsive containers to change how wide the content in your navbar.
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-md">
<a class="navbar-brand" href="#">Navbar</a>
</div>
</nav>
{{< /example >}}
## Placement
Use our [position utilities]({{< docsref "/utilities/position" >}}) to place navbars in non-static positions. Choose from fixed to the top, fixed to the bottom, or stickied to the top (scrolls with the page until it reaches the top, then stays there). Fixed navbars use `position: fixed`, meaning they're pulled from the normal flow of the DOM and may require custom CSS (e.g., `padding-top` on the `<body>`) to prevent overlap with other elements.
Also note that **`.sticky-top` uses `position: sticky`, which [isn't fully supported in every browser](https://caniuse.com/#feat=css-sticky)**.
{{< example >}}
<nav class="navbar navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Default</a>
</div>
</nav>
{{< /example >}}
{{< example >}}
<nav class="navbar fixed-top navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Fixed top</a>
</div>
</nav>
{{< /example >}}
{{< example >}}
<nav class="navbar fixed-bottom navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Fixed bottom</a>
</div>
</nav>
{{< /example >}}
{{< example >}}
<nav class="navbar sticky-top navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Sticky top</a>
</div>
</nav>
{{< /example >}}
## Responsive behaviors
Navbars can utilize `.navbar-toggler`, `.navbar-collapse`, and `.navbar-expand{-sm|-md|-lg|-xl}` classes to change when their content collapses behind a button. In combination with other utilities, you can easily choose when to show or hide particular elements.
For navbars that never collapse, add the `.navbar-expand` class on the navbar. For navbars that always collapse, don't add any `.navbar-expand` class.
### Toggler
Navbar togglers are left-aligned by default, but should they follow a sibling element like a `.navbar-brand`, they'll automatically be aligned to the far right. Reversing your markup will reverse the placement of the toggler. Below are examples of different toggle styles.
With no `.navbar-brand` shown in lowest breakpoint:
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarTogglerDemo01" aria-controls="navbarTogglerDemo01" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarTogglerDemo01">
<a class="navbar-brand" href="#">Hidden brand</a>
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</li>
</ul>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success" type="submit">Search</button>
</form>
</div>
</div>
</nav>
{{< /example >}}
With a brand name shown on the left and toggler on the right:
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarTogglerDemo02" aria-controls="navbarTogglerDemo02" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarTogglerDemo02">
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</li>
</ul>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success" type="submit">Search</button>
</form>
</div>
</div>
</nav>
{{< /example >}}
With a toggler on the left and brand name on the right:
{{< example >}}
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarTogglerDemo03" aria-controls="navbarTogglerDemo03" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<a class="navbar-brand" href="#">Navbar</a>
<div class="collapse navbar-collapse" id="navbarTogglerDemo03">
<ul class="navbar-nav mr-auto mb-2 mb-lg-0">
<li class="nav-item active">
<a class="nav-link" aria-current="page" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</li>
</ul>
<form class="d-flex">
<input class="form-control mr-2" type="search" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success" type="submit">Search</button>
</form>
</div>
</div>
</nav>
{{< /example >}}
### External content
Sometimes you want to use the collapse plugin to trigger hidden content elsewhere on the page. Because our plugin works on the `id` and `data-target` matching, that's easily done!
{{< example >}}
<div class="collapse" id="navbarToggleExternalContent">
<div class="bg-dark p-4">
<h5 class="text-white h4">Collapsed content</h5>
<span class="text-muted">Toggleable via the navbar brand.</span>
</div>
</div>
<nav class="navbar navbar-dark bg-dark">
<div class="container-fluid">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarToggleExternalContent" aria-controls="navbarToggleExternalContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
</div>
</nav>
{{< /example >}}