Headings

The Heading feature enables support for headings. These are used by the creators to structure their documents. They also aid both the readers, making the content more organized and easier to read, and the search indexers scanning for crucial information.

Headings can easily be added with toolbar dropdown, buttons or with Markdown code as you type. They can also be cleared with the remove format feature.

# Heading levels

By default this feature is configured to support <h2>, <h3> and <h4> elements which are named: “Heading 1”, “Heading 2” and “Heading 3”, respectively. The rationale behind starting from <h2> is that <h1> should be reserved for the page’s main title and the page content will usually start from <h2>.

By default, when your editor build does not include the title plugin, a <h1> element pasted into the rich-text editor is converted to <h2> (“Heading 1”).

# Demo

Use the toolbar dropdown to style a heading, or type one or more # characters (depending on the heading level), followed by a space, to start a new heading with the autoformatting feature.

# Heading buttons

The heading feature lets you also use a set of heading buttons instead of the dropdown list. The toolbar buttons are configurable and it is possible to include a paragraph button, too. Compare the heading toolbar dropdown from the demo above with the heading buttons below to check the functionality and usability of this variation.

# Related features

There are more CKEditor 5 features that can help you format your content:

• Basic text styles – The essentials, like bold, italic and others.
• Document title – Clearly divide your content into a title and body.
• Block indentation – Set indentation for text blocks such as paragraphs or lists.
• Lists – Organize your content better with ordered and unordered lists you can style.
• Remove format – Easily clean basic text formatting.
• Autoformatting – Add formatting elements (such as headings) as you type with Markdown code.

# Configuration

# Configuring heading levels

You can configure which heading levels the editor will support and how they should be named in the Headings dropdown. Use the heading.options configuration option to do so.

For example, the following editor will support only two levels of headings — <h1> and <h2>:

<div id="editor">
    <h1>Heading 1</h1>
    <h2>Heading 2</h2>
    <p>This is <a href="https://ckeditor.com">CKEditor 5</a>.</p>
</div>

ClassicEditor
    .create( document.querySelector( '#editor' ), {
        heading: {
            options: [
                { model: 'paragraph', title: 'Paragraph', class: 'ck-heading_paragraph' },
                { model: 'heading1', view: 'h1', title: 'Heading 1', class: 'ck-heading_heading1' },
                { model: 'heading2', view: 'h2', title: 'Heading 2', class: 'ck-heading_heading2' }
            ]
        }
    } )
    .then( ... )
    .catch( ... );

# Configuring custom heading elements

It is also possible to define fully custom elements for headings by using the advanced format of the heading.options configuration option.

For example, the following editor will support the following two heading options at the same time: <h2 class="fancy"> and <h2>:

<style>
    /* Styles for the heading in the content and for the dropdown item. */
    h2.fancy, .ck.ck-button.ck-heading_heading2_fancy {
        color: #ff0050;
        font-size: 17px;
    }
</style>

<div id="snippet-custom-heading-levels">
    <h1>Heading 1</h1>
    <h2>Heading 2</h2>
    <h2 class="fancy">Fancy Heading 2</h2>
    <p>This is <a href="https://ckeditor.com">CKEditor 5</a>.</p>
</div>

ClassicEditor
    .create( document.querySelector( '#editor' ), {
        heading: {
            options: [
                { model: 'paragraph', title: 'Paragraph', class: 'ck-heading_paragraph' },
                { model: 'heading1', view: 'h1', title: 'Heading 1', class: 'ck-heading_heading1' },
                { model: 'heading2', view: 'h2', title: 'Heading 2', class: 'ck-heading_heading2' },
                {
                    model: 'headingFancy',
                    view: {
                        name: 'h2',
                        classes: 'fancy'
                    },
                    title: 'Heading 2 (fancy)',
                    class: 'ck-heading_heading2_fancy',

                    // It needs to be converted before the standard 'heading2'.
                    converterPriority: 'high'
                }
            ]
        }
    } )
    .then( ... )
    .catch( ... );

# Configuring toolbar buttons

In order to use individual toolbar buttons instead of the heading dropdown, you need to properly configure the feature. You also need to import proper UI elements; see the installation section for instructions on how to do it.

ClassicEditor
    .create( document.querySelector( '#editor' ), {
        toolbar: [ 'paragraph', 'heading1', 'heading2', 'heading3', 'heading4', 'heading5', 'heading6', '|', 'undo', 'redo' ],
        heading: {
            options: [
                { model: 'paragraph', title: 'Paragraph', class: 'ck-heading_paragraph' },
                { model: 'heading1', view: 'h1', title: 'Heading 1', class: 'ck-heading_heading1' },
                { model: 'heading2', view: 'h2', title: 'Heading 2', class: 'ck-heading_heading2' },
                { model: 'heading3', view: 'h3', title: 'Heading 3', class: 'ck-heading_heading3' },
                { model: 'heading4', view: 'h4', title: 'Heading 4', class: 'ck-heading_heading4' },
                { model: 'heading5', view: 'h5', title: 'Heading 5', class: 'ck-heading_heading5' },
                { model: 'heading6', view: 'h6', title: 'Heading 6', class: 'ck-heading_heading6' }
            ]
        }
    } )
    .then( ... )
    .catch( ... );

# Installation

To add this feature to your editor install the @ckeditor/ckeditor5-heading package:

npm install --save @ckeditor/ckeditor5-heading

And add it to your plugin list and toolbar configuration:

import Heading from '@ckeditor/ckeditor5-heading/src/heading';

ClassicEditor
    .create( document.querySelector( '#editor' ), {
        plugins: [ Heading, ... ],
        toolbar: [ 'heading', ... ]
    } )
    .then( ... )
    .catch( ... );

# Installation with toolbar heading buttons

In order to be able to configure the toolbar buttons for headings and paragraph, you need to import the following into your plugin list and configuration:

import HeadingButtonsUI from '@ckeditor/ckeditor5-heading/src/headingbuttonsui';
import ParagraphButtonUI from '@ckeditor/ckeditor5-paragraph/src/paragraphbuttonui';

# Common API

The Heading plugin registers:

• The 'heading' dropdown.

• The 'heading' command that accepts a value based on the heading.options configuration option.

  You can turn the currently selected block(s) to headings by executing one of these commands:

  editor.execute( 'heading', { value: 'heading2' } );
  

The HeadingButtonsUI plugin registers six UI button components that will execute the 'heading' command with the proper value of the value attribute:

• 'heading1'
• 'heading2'
• 'heading3'
• 'heading4'
• 'heading5'
• 'heading6'

The ParagraphButtonUI plugin registers the UI button component: 'paragraph'.

# Contribute

The source code of the feature is available on GitHub in https://github.com/ckeditor/ckeditor5/tree/master/packages/ckeditor5-heading.