---
layout: docs
title: Scrollspy
description: Automatically update Bootstrap navigation or list group components based on scroll position to indicate which link is currently active in the viewport.
group: components
toc: true
---

## How it works

Scrollspy has a few requirements to function properly:

- If you're building our JavaScript from source, it [requires `util.js`]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/javascript/#util).
- It must be used on a Bootstrap [nav component]({{ site.baseurl }}/docs/{{ site.docs_version }}/components/navs/) or [list group]({{ site.baseurl }}/docs/{{ site.docs_version }}/components/list-group/).
- Scrollspy requires `position: relative;` on the element you're spying on, usually the `<body>`.
- When spying on elements other than the `<body>`, be sure to have a `height` set and `overflow-y: scroll;` applied.
- Anchors (`<a>`) are required and must point to an element with that `id`.

When successfully implemented, your nav or list group will update accordingly, moving the `.active` class from one item to the next based on their associated targets.

## Example in navbar

Scroll the area below the navbar and watch the active class change. The dropdown items will be highlighted as well.

<div class="bd-example">
  <nav id="navbar-example2" class="navbar navbar-light bg-light">
    <a class="navbar-brand" href="#">Navbar</a>
    <ul class="nav nav-pills">
      <li class="nav-item">
        <a class="nav-link" href="#fat">@fat</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#mdo">@mdo</a>
      </li>
      <li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" data-toggle="dropdown" href="#" role="button" aria-haspopup="true" aria-expanded="false">Dropdown</a>
        <div class="dropdown-menu">
          <a class="dropdown-item" href="#one">one</a>
          <a class="dropdown-item" href="#two">two</a>
          <div role="separator" class="dropdown-divider"></div>
          <a class="dropdown-item" href="#three">three</a>
        </div>
      </li>
    </ul>
  </nav>
  <div data-spy="scroll" data-target="#navbar-example2" data-offset="0" class="scrollspy-example">
    <h4 id="fat">@fat</h4>
    <p>Ad leggings keytar, brunch id art party dolor labore. Pitchfork yr enim lo-fi before they sold out qui. Tumblr farm-to-table bicycle rights whatever. Anim keffiyeh carles cardigan. Velit seitan mcsweeney's photo booth 3 wolf moon irure. Cosby sweater lomo jean shorts, williamsburg hoodie minim qui you probably haven't heard of them et cardigan trust fund culpa biodiesel wes anderson aesthetic. Nihil tattooed accusamus, cred irony biodiesel keffiyeh artisan ullamco consequat.</p>
    <h4 id="mdo">@mdo</h4>
    <p>Veniam marfa mustache skateboard, adipisicing fugiat velit pitchfork beard. Freegan beard aliqua cupidatat mcsweeney's vero. Cupidatat four loko nisi, ea helvetica nulla carles. Tattooed cosby sweater food truck, mcsweeney's quis non freegan vinyl. Lo-fi wes anderson +1 sartorial. Carles non aesthetic exercitation quis gentrify. Brooklyn adipisicing craft beer vice keytar deserunt.</p>
    <h4 id="one">one</h4>
    <p>Occaecat commodo aliqua delectus. Fap craft beer deserunt skateboard ea. Lomo bicycle rights adipisicing banh mi, velit ea sunt next level locavore single-origin coffee in magna veniam. High life id vinyl, echo park consequat quis aliquip banh mi pitchfork. Vero VHS est adipisicing. Consectetur nisi DIY minim messenger bag. Cred ex in, sustainable delectus consectetur fanny pack iphone.</p>
    <h4 id="two">two</h4>
    <p>In incididunt echo park, officia deserunt mcsweeney's proident master cleanse thundercats sapiente veniam. Excepteur VHS elit, proident shoreditch +1 biodiesel laborum craft beer. Single-origin coffee wayfarers irure four loko, cupidatat terry richardson master cleanse. Assumenda you probably haven't heard of them art party fanny pack, tattooed nulla cardigan tempor ad. Proident wolf nesciunt sartorial keffiyeh eu banh mi sustainable. Elit wolf voluptate, lo-fi ea portland before they sold out four loko. Locavore enim nostrud mlkshk brooklyn nesciunt.</p>
    <h4 id="three">three</h4>
    <p>Ad leggings keytar, brunch id art party dolor labore. Pitchfork yr enim lo-fi before they sold out qui. Tumblr farm-to-table bicycle rights whatever. Anim keffiyeh carles cardigan. Velit seitan mcsweeney's photo booth 3 wolf moon irure. Cosby sweater lomo jean shorts, williamsburg hoodie minim qui you probably haven't heard of them et cardigan trust fund culpa biodiesel wes anderson aesthetic. Nihil tattooed accusamus, cred irony biodiesel keffiyeh artisan ullamco consequat.</p>
    <p>Keytar twee blog, culpa messenger bag marfa whatever delectus food truck. Sapiente synth id assumenda. Locavore sed helvetica cliche irony, thundercats you probably haven't heard of them consequat hoodie gluten-free lo-fi fap aliquip. Labore elit placeat before they sold out, terry richardson proident brunch nesciunt quis cosby sweater pariatur keffiyeh ut helvetica artisan. Cardigan craft beer seitan readymade velit. VHS chambray laboris tempor veniam. Anim mollit minim commodo ullamco thundercats.
    </p>
  </div>
</div>

{% highlight html %}
<nav id="navbar-example2" class="navbar navbar-light bg-light">
  <a class="navbar-brand" href="#">Navbar</a>
  <ul class="nav nav-pills">
    <li class="nav-item">
      <a class="nav-link" href="#fat">@fat</a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#mdo">@mdo</a>
    </li>
    <li class="nav-item dropdown">
      <a class="nav-link dropdown-toggle" data-toggle="dropdown" href="#" role="button" aria-haspopup="true" aria-expanded="false">Dropdown</a>
      <div class="dropdown-menu">
        <a class="dropdown-item" href="#one">one</a>
        <a class="dropdown-item" href="#two">two</a>
        <div role="separator" class="dropdown-divider"></div>
        <a class="dropdown-item" href="#three">three</a>
      </div>
    </li>
  </ul>
</nav>
<div data-spy="scroll" data-target="#navbar-example2" data-offset="0">
  <h4 id="fat">@fat</h4>
  <p>...</p>
  <h4 id="mdo">@mdo</h4>
  <p>...</p>
  <h4 id="one">one</h4>
  <p>...</p>
  <h4 id="two">two</h4>
  <p>...</p>
  <h4 id="three">three</h4>
  <p>...</p>
</div>
{% endhighlight %}

## Example with nested nav

Scrollspy also works with nested `.nav`s. If a nested `.nav` is `.active`, its parents will also be `.active`. Scroll the area next to the navbar and watch the active class change.

<div class="bd-example">
  <div class="row">
    <div class="col-4">
      <nav id="navbar-example3" class="navbar navbar-light bg-light flex-column">
        <a class="navbar-brand" href="#">Navbar</a>
        <nav class="nav nav-pills flex-column">
          <a class="nav-link" href="#item-1">Item 1</a>
          <nav class="nav nav-pills flex-column">
            <a class="nav-link ml-3 my-1" href="#item-1-1">Item 1-1</a>
            <a class="nav-link ml-3 my-1" href="#item-1-2">Item 1-2</a>
          </nav>
          <a class="nav-link" href="#item-2">Item 2</a>
          <a class="nav-link" href="#item-3">Item 3</a>
          <nav class="nav nav-pills flex-column">
            <a class="nav-link ml-3 my-1" href="#item-3-1">Item 3-1</a>
            <a class="nav-link ml-3 my-1" href="#item-3-2">Item 3-2</a>
          </nav>
        </nav>
      </nav>
    </div>
    <div class="col-8">
      <div data-spy="scroll" data-target="#navbar-example3" data-offset="0" class="scrollspy-example-2">
        <h4 id="item-1">Item 1</h4>
        <p>Ex consequat commodo adipisicing exercitation aute excepteur occaecat ullamco duis aliqua id magna ullamco eu. Do aute ipsum ipsum ullamco cillum consectetur ut et aute consectetur labore. Fugiat laborum incididunt tempor eu consequat enim dolore proident. Qui laborum do non excepteur nulla magna eiusmod consectetur in. Aliqua et aliqua officia quis et incididunt voluptate non anim reprehenderit adipisicing dolore ut consequat deserunt mollit dolore. Aliquip nulla enim veniam non fugiat id cupidatat nulla elit cupidatat commodo velit ut eiusmod cupidatat elit dolore.</p>
        <h5 id="item-1-1">Item 1-1</h5>
        <p>Amet tempor mollit aliquip pariatur excepteur commodo do ea cillum commodo Lorem et occaecat elit qui et. Aliquip labore ex ex esse voluptate occaecat Lorem ullamco deserunt. Aliqua cillum excepteur irure consequat id quis ea. Sit proident ullamco aute magna pariatur nostrud labore. Reprehenderit aliqua commodo eiusmod aliquip est do duis amet proident magna consectetur consequat eu commodo fugiat non quis. Enim aliquip exercitation ullamco adipisicing voluptate excepteur minim exercitation minim minim commodo adipisicing exercitation officia nisi adipisicing. Anim id duis qui consequat labore adipisicing sint dolor elit cillum anim et fugiat.</p>
        <h5 id="item-1-2">Item 2-2</h5>
        <p>Cillum nisi deserunt magna eiusmod qui eiusmod velit voluptate pariatur laborum sunt enim. Irure laboris mollit consequat incididunt sint et culpa culpa incididunt adipisicing magna magna occaecat. Nulla ipsum cillum eiusmod sint elit excepteur ea labore enim consectetur in labore anim. Proident ullamco ipsum esse elit ut Lorem eiusmod dolor et eiusmod. Anim occaecat nulla in non consequat eiusmod velit incididunt.</p>
        <h4 id="item-2">Item 2</h4>
        <p>Quis magna Lorem anim amet ipsum do mollit sit cillum voluptate ex nulla tempor. Laborum consequat non elit enim exercitation cillum aliqua consequat id aliqua. Esse ex consectetur mollit voluptate est in duis laboris ad sit ipsum anim Lorem. Incididunt veniam velit elit elit veniam Lorem aliqua quis ullamco deserunt sit enim elit aliqua esse irure. Laborum nisi sit est tempor laborum mollit labore officia laborum excepteur commodo non commodo dolor excepteur commodo. Ipsum fugiat ex est consectetur ipsum commodo tempor sunt in proident.</p>
        <h4 id="item-3">Item 3</h4>
        <p>Quis anim sit do amet fugiat dolor velit sit ea ea do reprehenderit culpa duis. Nostrud aliqua ipsum fugiat minim proident occaecat excepteur aliquip culpa aute tempor reprehenderit. Deserunt tempor mollit elit ex pariatur dolore velit fugiat mollit culpa irure ullamco est ex ullamco excepteur.</p>
        <h5 id="item-3-1">Item 3-1</h5>
        <p>Deserunt quis elit Lorem eiusmod amet enim enim amet minim Lorem proident nostrud. Ea id dolore anim exercitation aute fugiat labore voluptate cillum do laboris labore. Ex velit exercitation nisi enim labore reprehenderit labore nostrud ut ut. Esse officia sunt duis aliquip ullamco tempor eiusmod deserunt irure nostrud irure. Ullamco proident veniam laboris ea consectetur magna sunt ex exercitation aliquip minim enim culpa occaecat exercitation. Est tempor excepteur aliquip laborum consequat do deserunt laborum esse eiusmod irure proident ipsum esse qui.</p>
        <h5 id="item-3-2">Item 3-2</h5>
        <p>Labore sit culpa commodo elit adipisicing sit aliquip elit proident voluptate minim mollit nostrud aute reprehenderit do. Mollit excepteur eu Lorem ipsum anim commodo sint labore Lorem in exercitation velit incididunt. Occaecat consectetur nisi in occaecat proident minim enim sunt reprehenderit exercitation cupidatat et do officia. Aliquip consequat ad labore labore mollit ut amet. Sit pariatur tempor proident in veniam culpa aliqua excepteur elit magna fugiat eiusmod amet officia.</p>
      </div>
    </div>
  </div>
</div>

{% highlight html %}
<nav id="navbar-example3" class="navbar navbar-light bg-light">
  <a class="navbar-brand" href="#">Navbar</a>
  <nav class="nav nav-pills flex-column">
    <a class="nav-link" href="#item-1">Item 1</a>
    <nav class="nav nav-pills flex-column">
      <a class="nav-link ml-3 my-1" href="#item-1-1">Item 1-1</a>
      <a class="nav-link ml-3 my-1" href="#item-1-2">Item 1-2</a>
    </nav>
    <a class="nav-link" href="#item-2">Item2</a>
    <a class="nav-link" href="#item-3">Item3</a>
    <nav class="nav nav-pills flex-column">
      <a class="nav-link ml-3 my-1" href="#item-3-1">Item 3-1</a>
      <a class="nav-link ml-3 my-1" href="#item-3-2">Item 3-2</a>
    </nav>
  </nav>
</nav>

<div data-spy="scroll" data-target="#navbar-example3" data-offset="0">
  <h4 id="item-1">Item 1</h4>
  <p>...</p>
  <h5 id="item-1-1">Item 1-1</h5>
  <p>...</p>
  <h5 id="item-1-2">Item 2-2</h5>
  <p>...</p>
  <h4 id="item-2">Item 2</h4>
  <p>...</p>
  <h4 id="item-3">Item 3</h4>
  <p>...</p>
  <h5 id="item-3-1">Item 3-1</h5>
  <p>...</p>
  <h5 id="item-3-2">Item 3-2</h5>
  <p>...</p>
</div>
{% endhighlight %}

## Example with list-group

Scrollspy also works with `.list-group`s. Scroll the area next to the list group and watch the active class change.

<div class="bd-example">
  <div class="row">
    <div class="col-4">
      <div id="list-example" class="list-group">
        <a class="list-group-item list-group-item-action" href="#list-item-1">Item 1</a>
        <a class="list-group-item list-group-item-action" href="#list-item-2">Item2</a>
        <a class="list-group-item list-group-item-action" href="#list-item-3">Item 3</a>
        <a class="list-group-item list-group-item-action" href="#list-item-4">Item 4</a>
      </div>
    </div>
    <div class="col-8">
      <div data-spy="scroll" data-target="#list-example" data-offset="0" class="scrollspy-example">
        <h4 id="list-item-1">Item 1</h4>
        <p>Ex consequat commodo adipisicing exercitation aute excepteur occaecat ullamco duis aliqua id magna ullamco eu. Do aute ipsum ipsum ullamco cillum consectetur ut et aute consectetur labore. Fugiat laborum incididunt tempor eu consequat enim dolore proident. Qui laborum do non excepteur nulla magna eiusmod consectetur in. Aliqua et aliqua officia quis et incididunt voluptate non anim reprehenderit adipisicing dolore ut consequat deserunt mollit dolore. Aliquip nulla enim veniam non fugiat id cupidatat nulla elit cupidatat commodo velit ut eiusmod cupidatat elit dolore.</p>
        <h4 id="list-item-2">Item 2</h4>
        <p>Quis magna Lorem anim amet ipsum do mollit sit cillum voluptate ex nulla tempor. Laborum consequat non elit enim exercitation cillum aliqua consequat id aliqua. Esse ex consectetur mollit voluptate est in duis laboris ad sit ipsum anim Lorem. Incididunt veniam velit elit elit veniam Lorem aliqua quis ullamco deserunt sit enim elit aliqua esse irure. Laborum nisi sit est tempor laborum mollit labore officia laborum excepteur commodo non commodo dolor excepteur commodo. Ipsum fugiat ex est consectetur ipsum commodo tempor sunt in proident.</p>
        <h4 id="list-item-3">Item 3</h4>
        <p>Quis anim sit do amet fugiat dolor velit sit ea ea do reprehenderit culpa duis. Nostrud aliqua ipsum fugiat minim proident occaecat excepteur aliquip culpa aute tempor reprehenderit. Deserunt tempor mollit elit ex pariatur dolore velit fugiat mollit culpa irure ullamco est ex ullamco excepteur.</p>
        <h4 id="list-item-4">Item 4</h4>
        <p>Quis anim sit do amet fugiat dolor velit sit ea ea do reprehenderit culpa duis. Nostrud aliqua ipsum fugiat minim proident occaecat excepteur aliquip culpa aute tempor reprehenderit. Deserunt tempor mollit elit ex pariatur dolore velit fugiat mollit culpa irure ullamco est ex ullamco excepteur.</p>
      </div>
    </div>
  </div>
</div>

{% highlight html %}
<div id="list-example" class="list-group">
  <a class="list-group-item list-group-item-action" href="#list-item-1">Item 1</a>
  <a class="list-group-item list-group-item-action" href="#list-item-2">Item2</a>
  <a class="list-group-item list-group-item-action" href="#list-item-3">Item 3</a>
  <a class="list-group-item list-group-item-action" href="#list-item-4">Item 4</a>
</div>
<div data-spy="scroll" data-target="#list-example" data-offset="0" class="scrollspy-example">
  <h4 id="list-item-1">Item 1</h4>
  <p>...</p>
  <h4 id="list-item-2">Item 2</h4>
  <p>...</p>
  <h4 id="list-item-3">Item 3</h4>
  <p>...</p>
  <h4 id="list-item-4">Item 4</h4>
  <p>...</p>
</div>
{% endhighlight %}


## Usage

### Via data attributes

To easily add scrollspy behavior to your topbar navigation, add `data-spy="scroll"` to the element you want to spy on (most typically this would be the `<body>`). Then add the `data-target` attribute with the ID or class of the parent element of any Bootstrap `.nav` component.

{% highlight css %}
body {
  position: relative;
}
{% endhighlight %}

{% highlight html %}
<body data-spy="scroll" data-target="#navbar-example">
  ...
  <div id="navbar-example">
    <ul class="nav nav-tabs" role="tablist">
      ...
    </ul>
  </div>
  ...
</body>
{% endhighlight %}

### Via JavaScript

After adding `position: relative;` in your CSS, call the scrollspy via JavaScript:

{% highlight js %}
$('body').scrollspy({ target: '#navbar-example' })
{% endhighlight %}

{% callout danger %}
#### Resolvable ID targets required

Navbar links must have resolvable id targets. For example, a `<a href="#home">home</a>` must correspond to something in the DOM like `<div id="home"></div>`.
{% endcallout %}

{% callout info %}
#### Non-`:visible` target elements ignored

Target elements that are not [`:visible` according to jQuery](https://api.jquery.com/visible-selector/) will be ignored and their corresponding nav items will never be highlighted.
{% endcallout %}

### Methods

#### `.scrollspy('refresh')`

When using scrollspy in conjunction with adding or removing of elements from the DOM, you'll need to call the refresh method like so:

{% highlight js %}
$('[data-spy="scroll"]').each(function () {
  var $spy = $(this).scrollspy('refresh')
})
{% endhighlight %}

#### `.scrollspy('dispose')`

Destroys an element's scrollspy.

### Options

Options can be passed via data attributes or JavaScript. For data attributes, append the option name to `data-`, as in `data-offset=""`.

<table class="table table-bordered table-striped">
  <thead>
    <tr>
      <th style="width: 100px;">Name</th>
      <th style="width: 100px;">Type</th>
      <th style="width: 50px;">Default</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>offset</td>
      <td>number</td>
      <td>10</td>
      <td>Pixels to offset from top when calculating position of scroll.</td>
    </tr>
  </tbody>
</table>

### Events

<table class="table table-bordered table-striped">
  <thead>
    <tr>
      <th style="width: 150px;">Event Type</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>activate.bs.scrollspy</td>
      <td>This event fires on the scroll element whenever a new item becomes activated by the scrollspy.</td>
    </tr>
  </tbody>
</table>

{% highlight js %}
$('[data-spy="scroll"]').on('activate.bs.scrollspy', function () {
  // do something…
})
{% endhighlight %}
