Options

Swup has several options that can be passed in during initialization.

Defaults

These are the default options. See below for details on each option.

const swup = new Swup({
  animateHistoryBrowsing: false,
  animationSelector: '[class*="transition-"]',
  animationScope: 'html',
  cache: true,
  containers: ['#swup'],
  hooks: {},
  ignoreVisit: (url, { el } = {}) => el?.closest('[data-no-swup]'),
  linkSelector: 'a[href]',
  linkToSelf: 'scroll',
  native: false,
  plugins: [],
  resolveUrl: (url) => url,
  requestHeaders: {
    'X-Requested-With': 'swup',
    'Accept': 'text/html, application/xhtml+xml'
  },
  skipPopStateHandling: (event) => event.state?.source !== 'swup',
  timeout: 0
});

const swup = new Swup({
  animateHistoryBrowsing: false,
  animationSelector: '[class*="transition-"]',
  animationScope: 'html',
  cache: true,
  containers: ['#swup'],
  hooks: {},
  ignoreVisit: (url, { el } = {}) => el?.closest('[data-no-swup]'),
  linkSelector: 'a[href]',
  linkToSelf: 'scroll',
  native: false,
  plugins: [],
  resolveUrl: (url) => url,
  requestHeaders: {
    'X-Requested-With': 'swup',
    'Accept': 'text/html, application/xhtml+xml'
  },
  skipPopStateHandling: (event) => event.state?.source !== 'swup',
  timeout: 0
});

The selector for detecting animation timing. Swup will wait for all CSS transitions and keyframe animations to finish on these elements before swapping in the content of the new page. The default option will select all elements with class names beginning in transition-.

{
  animationSelector: '[class*="transition-"]'
}

{
  animationSelector: '[class*="transition-"]'
}

animationScope

The elements on which swup will add the animation classes for styling the different phases of the in/out animation. By default, it will add those classes to the html tag. This is great for most use cases and the recommended way to use swup.

{
  animationScope: 'html'
}

{
  animationScope: 'html'
}

<html class="is-animating is-leaving"></html>

<html class="is-animating is-leaving"></html>

Setting this option to containers will add the classes on the content containers themselves instead.

{
  animationScope: 'containers'
}

{
  animationScope: 'containers'
}

<main id="swup" class="is-animating is-leaving">Content</main>

<main id="swup" class="is-animating is-leaving">Content</main>

containers

The content containers to be replaced on page visits. Usually the <main> element with the content of the page, but can include any other elements that are present across all pages. Defaults to a single container of id #swup.

Adding containers here allows animating one set of elements while replacing other parts of the page without animation, e.g. a global site navigation that will not fade out but still needs to update to reflect language changes.

{
  containers: ['#swup']
}

{
  containers: ['#swup']
}

cache

The built-in cache keeps previously loaded pages in memory. This improves speed but can be disabled for highly dynamic sites that need up-to-date responses on each request. Defaults to true.

{
  cache: true
}

{
  cache: true
}

hooks

An object of hook handlers to register. For details and a few more examples, see the section on registering all hook handlers at once.

{
  hooks: {
    'visit:start': () => console.log('start'),
    'visit:end': () => console.log('end')
  }
}

{
  hooks: {
    'visit:start': () => console.log('start'),
    'visit:end': () => console.log('end')
  }
}

ignoreVisit

Allows ignoring specific visits via callback. By default, swup will ignore links with a data-no-swup attribute on itself or any parent element.

The callback takes a relative URL of the new page, as well as the element and event that triggered the visit. Note that element and event will be undefined if navigating via swup.navigate(url).

{
  ignoreVisit: (url, { el, event } = {}) => el?.closest('[data-no-swup]')
}

{
  ignoreVisit: (url, { el, event } = {}) => el?.closest('[data-no-swup]')
}

linkSelector

The link elements that trigger visits. By default, all a elements with an href attribute will receive clicks.

{
  linkSelector: 'a[href]'
}

{
  linkSelector: 'a[href]'
}

To let swup take over clicks on map areas or SVG links, append the selector:

{
  linkSelector: 'a[href], area[href], svg a[*|href]'
}

{
  linkSelector: 'a[href], area[href], svg a[*|href]'
}

linkToSelf

How swup handles links that lead to the currently active URL. By default, it will scroll to the top without actually performing a navigation. Pass in navigate to treat these links like any other link and perform a regular navigation.

{
  linkToSelf: 'navigate'
}

{
  linkToSelf: 'navigate'
}

native

Enable native animations using the View Transitions API. This will toggle the class swup-native on the HTML element if View Transitions are supported by the user's browsers. Learn more about native view transitions.

requestHeaders

The custom headers that get sent along with each swup request.

{
  requestHeaders: {
    'X-Requested-With': 'swup', // identify swup requests
    'Accept': 'text/html, application/xhtml+xml' // define expected response
  }
}

{
  requestHeaders: {
    'X-Requested-With': 'swup', // identify swup requests
    'Accept': 'text/html, application/xhtml+xml' // define expected response
  }
}

resolveUrl

Rewrite URLs before loading them. An advanced way of ignoring certain visits by mapping different paths to a single path and treating them as one resource for fetching pages and restoring scroll positions. The callback receives and returns a relative URL.

An example use case would be a project listing: the server always sends the complete list of projects and filtering is done client-side based on query params. You'll want to handle any visits between /projects/?sort=date and /projects/?sort=title yourself, telling swup nothing has changed and no page load is necessary.

{
  resolveUrl: (url) => {
    if (url.startsWith('/projects/?')) {
      return '/projects/';
    }
    return url;
  }
}

{
  resolveUrl: (url) => {
    if (url.startsWith('/projects/?')) {
      return '/projects/';
    }
    return url;
  }
}

The option defaults to (url) => url.

skipPopStateHandling

Swup will only handle backward/forward visits to history entries it has created itself. Any visits to entries without a custom source property will be ignored and handled by the browser instead. To modify this behavior, provide a custom callback function that receives the popstate event and returns a boolean.

{
  skipPopStateHandling: (event) => event.state?.source !== 'swup'
}

{
  skipPopStateHandling: (event) => event.state?.source !== 'swup'
}

timeout

Swup allows setting a fetch timeout in milliseconds. If a page takes longer to load than specified, swup triggers a fetch:timeout hook and defers to a standard browser page load. Disabled by default.

{
  timeout: 10_000
}

{
  timeout: 10_000
}

animateHistoryBrowsing

Swup will skip animations for visits triggered by the back/forward button. If you do require animations on history visits, set this to true. Swup will add the class is-popstate to the html tag during those animations. Defaults to false.

{
  animateHistoryBrowsing: false
}

{
  animateHistoryBrowsing: false
}