Demo

Smooth Scroll Plugin

Allows for easy implementation of smooth scrolling for same-page links.

NPM

Note: Version 2.0+ of this plugin requires jQuery version 1.7 or greater.

Download

Using npm:

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npm install jquery-smooth-scroll

The old-fashioned way:

Go to the following URL in your browser and copy/paste the code into your own file: https://raw.githubusercontent.com/kswedberg/jquery-smooth-scroll/master/jquery.smooth-scroll.js

Demo

You can try a bare-bones demo at kswedberg.github.io/jquery-smooth-scroll/demo/

Features

$.fn.smoothScroll

Options

The following options, shown with their default values, are available for both $.fn.smoothScroll and $.smoothScroll:

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{
  offset: 0,
 
  // one of 'top' or 'left'
  direction: 'top',
 
  // only use if you want to override default behavior
  scrollTarget: null,
 
  // string to use as selector for event delegation
  delegateSelector: null,
 
  // fn(opts) function to be called before scrolling occurs.
  // `this` is the element(s) being scrolled
  beforeScroll: function() {},
 
  // fn(opts) function to be called after scrolling occurs.
  // `this` is the triggering element
  afterScroll: function() {},
 
  // easing name. jQuery comes with "swing" and "linear." For others, you'll need an easing plugin
  // from jQuery UI or elsewhere
  easing: 'swing',
 
  // speed can be a number or 'auto'
  // if 'auto', the speed will be calculated based on the formula:
  // (current scroll position - target scroll position) / autoCoeffic
  speed: 400,
 
  // autoCoefficent: Only used when speed set to "auto".
  // The higher this number, the faster the scroll speed
  autoCoefficient: 2,
 
  // $.fn.smoothScroll only: whether to prevent the default click action
  preventDefault: true
 
}

The options object for $.fn.smoothScroll can take two additional properties: exclude and excludeWithin. The value for both of these is an array of selectors, DOM elements or jQuery objects. Default value for both is an empty array.

Setting options after initial call

If you need to change any of the options after you've already called .smoothScroll(), you can do so by passing the "options" string as the first argument and an options object as the second.

$.smoothScroll

Additional Option

The following option, in addition to those listed for $.fn.smoothScroll above, is available for $.smoothScroll:

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{
  // The jQuery set of elements you wish to scroll.
  //  if null (default), $('html, body').firstScrollable() is used.
  scrollElement: null
}

$.fn.scrollable

$.fn.firstScrollable

Examples

Scroll down one "page" at a time (v2.1+)

With smoothScroll version 2.1 and later, you can use the "relative string" syntax to scroll an element or the document a certain number of pixels relative to its current position. The following code will scroll the document down one page at a time when the user clicks the ".pagedown" button:

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$('button.pagedown').on('click', function() {
  $.smoothScroll('+=' + $(window).height());
});

Smooth scrolling on page load

If you want to scroll to an element when the page loads, use $.smoothScroll() in a script at the end of the body or use $(document).ready(). To prevent the browser from automatically scrolling to the element on its own, your link on page 1 will need to include a fragment identifier that does not match an element id on page 2. To ensure that users without JavaScript get to the same element, you should modify the link's hash on page 1 with JavaScript. Your script on page 2 will then modify it back to the correct one when you call $.smoothScroll().

For example, let's say you want to smooth scroll to <div id="scrolltome"></div> on page-2.html. For page-1.html, your script might do the following:

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$('a[href="page-2.html#scrolltome"]').attr('href', function() {
  var hrefParts = this.href.split(/#/);
  hrefParts[1] = 'smoothScroll' + hrefParts[1];
  return hrefParts.join('#');
});

Then for page-2.html, your script would do this:

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// Call $.smoothScroll if location.hash starts with "#smoothScroll"
var reSmooth = /^#smoothScroll/;
var id;
if (reSmooth.test(location.hash)) {
  // Strip the "#smoothScroll" part off (and put "#" back on the beginning)
  id = '#' + location.hash.replace(reSmooth, '');
  $.smoothScroll({scrollTarget: id});
}

Focus element after scrolling to it.

Imagine you have a link to a form somewhere on the same page. When the user clicks the link, you want the user to be able to begin interacting with that form. With the smoothScroll plugin, you can use the afterScroll callback function. Here is an example that focuses the first input within the form after scrolling to the form:

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$('a.example').smoothScroll({
  afterScroll: function(options) {
    $(options.scrollTarget).find('input')[0].focus();
  }
});

For accessibility reasons, it might make sense to focus any element you scroll to, even if it's not a natively focusable element. To do so, you could add a tabIndex attribute to the target element:

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$('a.example').smoothScroll({
  afterScroll: function(options) {
    var $tgt = $(options.scrollTarget);
    $tgt.attr('tabIndex', '0');
    // Using $tgt[0] allows us to call .focus() on the DOM node itself, not the jQuery collection
    $tgt[0].focus();
  }
});

Notes

Contributing

Thank you! Please consider the following when working on this repo before you submit a pull request: