Block library for the WordPress editor.


Install the module

npm install @wordpress/block-library --save

This package assumes that your code will run in an ES2015+ environment. If you’re using an environment that has limited or no support for such language features and APIs, you should include the polyfill shipped in @wordpress/babel-preset-default in your code.



Function to register core blocks provided by the block editor.


import { registerCoreBlocks } from '@wordpress/block-library';



  • blocks Array: An optional array of the core blocks being registered.

Registering individual blocks

  1. When you only care about registering the block when file gets imported:
    import '@wordpress/block-library/build-module/verse/init';
  2. When you want to use the reference to the block after it gets automatically registered:
    import verseBlock from '@wordpress/block-library/build-module/verse/init';
  3. When you need a full control over when the block gets registered:
    import { init } from '@wordpress/block-library/build-module/verse';
    const verseBlock = init();

Contributing to this package

This is an individual package that’s part of the Gutenberg project. The project is organized as a monorepo. It’s made up of multiple self-contained software packages, each with a specific purpose. The packages in this monorepo are published to npm and used by WordPress as well as other software projects.

To find out more about contributing to this package or Gutenberg as a whole, please read the project’s main contributor guide.

Adding new blocks

⚠️ Adding new blocks to this package requires additional steps!

  1. Do not forget to register a new core block in the index.js file of this package. For example, if you were to add the new core block called core/blinking-paragraph, you would have to add something like:
    // packages/block-library/src/index.js
    import * as blinkingParagraph from './blinking-paragraph';

    Then add blinkingParagraph to the list in the getAllBlocks() function.

    If it’s experimental, add the following property to block.json:

        "__experimental": "true"
  2. Register the block in the gutenberg_reregister_core_block_types() function of the lib/blocks.php file. Add it to the block_folders array if it’s a static block or to the block_names array if it’s a dynamic block.

  3. Add init.js file to the directory of the new block:

     * Internal dependencies
    import { init } from './';
    export default init();

    This file is used when using the option to register individual block from the @wordpress/block-library package.

  4. If a view.js file (or a file prefixed with view, e.g. view-example.js) is present in the block’s directory, this file will be built along other assets, making it available to load from the browser. You only need to reference a view.min.js (notice the different file extension) file in the block.json file as follows:

        "viewScript": "file:./view.min.js"

    This file will get automatically loaded when the static block is present on the front end. For dynamic block, you need to manually enqueue the view script in render_callback of the block, example:

    function render_block_core_blinking_paragraph( $attributes, $content ) {
        $should_load_view_script = ! empty( $attributes['isInteractive'] ) && ! wp_script_is( 'wp-block-blinking-paragraph-view' );
        if ( $should_load_view_script ) {
            wp_enqueue_script( 'wp-block-blinking-paragraph-view' );
        return $content;

Naming convention for PHP functions

All PHP function names declared within the subdirectories of the packages/block-library/src/ directory should start with one of the following prefixes:

  • block_core_<directory_name>
  • render_block_core_<directory_name>
  • register_block_core_<directory_name>

In this context, <directory_name> represents the name of the directory where the corresponding .php file is located.
The directory name is converted to lowercase, and any characters except for letters and digits are replaced with underscores.


For the PHP functions declared in the packages/block-library/src/my-block/index.php file, the correct prefixes would be:

  • block_core_my_block
  • render_block_core_my_block
  • register_block_core_my_block

Using plugin-specific prefixes/suffixes

Unlike in PHP code in the /lib directory, you should generally avoid applying plugin-specific prefixes/suffixes such as gutenberg_ to functions and other code in block PHP files.

There are times, however, when blocks may need to use Gutenberg functions even when a Core-equivalent exists, for example, where a Gutenberg function relies on code that is only available in the plugin.

In such cases, you can use the corresponding Core wp_ function in the block PHP code, and add its name to a list of prefixed functions in the Webpack configuration file.

At build time, Webpack will search for wp_ functions in that list and replace them with their gutenberg_ equivalents. This process ensures that the plugin calls the gutenberg_ functions, but the block will still call the Core wp_ function when updates are back ported.

Webpack assumes that, prefixes aside, the functions’ names are identical: wp_get_something_useful() will be replaced with gutenberg_get_something_useful().