Blocks for reusing content across posts.

core/block

Synced pattern (formerly "reusable block").

References a wp_block post that can be reused across the site. Changes to the pattern update everywhere it’s used.

Attributes:

• ref (integer) — Pattern post ID
• content (object) — Overridable content (since 6.5)

Supports: className, customClassName: false, html: false, inserter: false, renaming: false

How It Works

1. User creates synced pattern → saved as wp_block post type
2. Block stores reference to post ID
3. When rendered, fetches and renders the wp_block post content
4. All instances stay in sync

Content Overrides (6.5+)

Synced patterns can have "overridable" content:

{
  "ref": 123,
  "content": {
    "abc123": {
      "content": "Custom text for this instance"
    }
  }
}

Block attributes with "metadata": { "bindings": { "content": { "source": "core/pattern-overrides" } } } can be overridden per-instance while keeping the pattern synced.

Database Storage

Categories

Patterns can be categorized using wp_pattern_category taxonomy.

REST API

• GET /wp/v2/blocks — List patterns
• POST /wp/v2/blocks — Create pattern
• GET /wp/v2/blocks/{id} — Get pattern
• PUT /wp/v2/blocks/{id} — Update pattern
• DELETE /wp/v2/blocks/{id} — Delete pattern

core/pattern

Pattern placeholder (internal use only).

Used during pattern insertion to temporarily hold the pattern reference before it’s replaced with actual block content.

Attributes:

• slug (string) — Pattern slug (e.g., theme-slug/pattern-name)

Supports:

• inserter: false — Not shown in inserter
• html: false — No HTML editing
• customClassName: false — No custom class

How It Works

1. User inserts pattern from inserter
2. core/pattern block created with slug
3. Editor immediately fetches pattern content
4. Block replaced with actual pattern blocks

This is a transient block — you won’t see it in saved content.

Pattern vs Reusable Block

Creating Patterns

Synced (Reusable):

wp.data.dispatch('core').saveEntityRecord('postType', 'wp_block', {
  title: 'My Pattern',
  content: '<!-- wp:paragraph --><p>Hello</p><!-- /wp:paragraph -->',
  status: 'publish'
});

Unsynced (Theme Pattern):
In theme’s patterns/ directory:

<?php
/**
 * Title: My Pattern
 * Slug: theme-slug/my-pattern
 * Categories: featured
 */
?>
<!-- wp:paragraph -->
<p>Hello</p>
<!-- /wp:paragraph -->