Common and experimental components that are not yet part of the GOV.UK Design System

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GOV.UK Prototype Components · test
GOV.UK Prototype Components contains the code you need to use common or experimental components that are not yet in the GOV.UK Design System.
These components are currently experimental and more research is needed to validate them.
| Component | Description | | - | - | | xGovukAutocomplete | Implements the Accessible autocomplete pattern to enhance a fixed list of options provided by a <select> element. | | xGovukMasthead | Implements the masthead component used on many GOV.UK product pages. | | xGovukPrimaryNavigation | Implements the primary navigation component used on the GOV.UK Design System website. | | xGovukRelatedNavigation | Implements related navigation component found in the govuk_publishing_components gem. | | xGovukSubNavigation | Implements the sub navigation component used on the GOV.UK Design System website. | | xGovukSummaryCard | Implements a component proposed for inclusion in the GOV.UK Design System. | | xGovukTaskList | Implements the task list page pattern documented on the GOV.UK Design System. |
Two JavaScript-only modules are also provided:
| Module | Description | | - | - | | Edge | Define the edges of your prototype for research. | | Warn on unsaved changes | Warn users if they try to leave a page without saving changes to a form. |
Prior to v1.0.0, this project included a collection of decorated form components. These can now be found in the govuk-decorated-components package.


Node.js v16 or later.


These components are included by default with the GOV.UK Prototype Rig.

npm install govuk-prototype-components --save

Usage with the GOV.UK Prototype Kit

Add the component imports to app/views/layout.html, directly after the imports from GOV.UK Frontend:
{% raw %}{% from "x-govuk/components/autocomplete/macro.njk" import xGovukAutocomplete with context %}
{% from "x-govuk/components/masthead/macro.njk" import xGovukMasthead %}
{% from "x-govuk/components/primary-navigation/macro.njk" import xGovukPrimaryNavigation %}
{% from "x-govuk/components/related-navigation/macro.njk" import xGovukRelatedNavigation %}
{% from "x-govuk/components/sub-navigation/macro.njk" import xGovukSubNavigation %}
{% from "x-govuk/components/summary-card/macro.njk" import xGovukSummaryCard %}
{% from "x-govuk/components/task-list/macro.njk" import xGovukTaskList %}{% endraw %}

To initialise those components which use JavaScript, add the following line to app/assets/javascript/application.js:
window.GOVUKPrototypeKit.documentReady(() => {
  // Add JavaScript here
+   window.GOVUKPrototypeComponents.initAll()

Advanced usage


To import all the Sass rules from GOV.UK Prototype Components, add the following to your Sass file:
@import "node_modules/govuk-prototype-components/x-govuk/all";

You can also import Sass rules for an individual component. For example, to import styles for the masthead component, add the following to your Sass file:
@import "node_modules/govuk-prototype-components/x-govuk/components/masthead/masthead";


To import the JavaScript for the GOV.UK Prototype Components, you can either:
  • add the GOV.UK Prototype Components JavaScript file to your HTML
  • import the JavaScript using a bundler like Webpack

Add the JavaScript file to your HTML

If you decide to add the JavaScript to your HTML, first either:
  • set up your routing so that requests for the JavaScript file are served from node_modules/govuk-prototype-components/x-govuk/all.js
  • copy the node_modules/govuk-prototype-components/x-govuk/all.js file into your application

Then import the JavaScript file before the closing </body> tag of your HTML page or page template, and run the initAll function to initialise all the components.
  <script src="<YOUR-APP>/<YOUR-JS-FILE>.js"></script>

Import JavaScript using ES modules

If you decide to import using a bundler, use import to import all GOV.UK Prototype Components, then run the initAll function to initialise them:
import { initAll } from 'govuk-prototype-components'


You can also import the JavaScript for an individual component. For example, to import the autocomplete component, add the following to your JavaScript file:
import { Autocomplete } from 'govuk-prototype-components'

const myAutocomplete = document.querySelector('#my-autocomplete')
new Autocomplete(myAutocomplete).init()

Import JavaScript using Common JS

If you’re using a bundler that uses CommonJS (like Browserify), use require:
const GOVUKPrototypeComponents = require('govuk-prototype-components')


It is not possible to import individual components using CommonJS.