WordPress Gutenberg Blocks: Complete Guide 2026

Published April 21, 2026

WordPress Gutenberg Blocks Guide

Gutenberg, WordPress's block editor, has matured into a powerful content system. Understanding blocks deeply — not just the basics — unlocks faster content creation, consistent design, and a smoother path to Full Site Editing.

Core Block Categories

WordPress ships with 90+ core blocks organized into categories: Text (paragraphs, headings, lists, quotes, code), Media (image, video, audio, gallery, cover), Design (columns, group, spacer, separator), Widgets (search, calendar, latest posts), and Embeds (YouTube, Twitter, Spotify).

Block Patterns

Block patterns are pre-composed layouts combining multiple blocks — a hero section, a two-column feature grid, a testimonial layout. Access them via the Patterns tab in the block inserter. Create custom patterns in your theme or plugin using register_block_pattern() for your team to reuse consistently.

Reusable Blocks

Convert any block or group of blocks into a Reusable Block. Changes to the reusable block update it everywhere it appears — ideal for CTAs, disclaimer text, or contact information. In WordPress 6.3+, reusable blocks were renamed "Synced Patterns" with enhanced management options.

Block Locking

Lock blocks to prevent editors from moving or deleting them. Useful for maintaining layout consistency on team sites. Combine block locking with a custom template to create editor-friendly page layouts where content areas are clearly defined.

Full Site Editing (FSE)

Block themes enable Full Site Editing — editing headers, footers, sidebars, and global styles with the block editor. The Site Editor (Appearance → Editor) replaces the Customizer for FSE-compatible themes. Theme.json controls global styles, spacing, typography, and color palettes across your entire site.

Creating Custom Blocks

The @wordpress/create-block scaffold generates the boilerplate for a custom block. Blocks use React for their editor interface and PHP for server-side rendering. The block.json manifest declares attributes, styles, and scripts. For simpler use cases, consider the Advanced Custom Fields Blocks feature or a block library plugin before writing custom code.

Performance Considerations

Each block type loads its own CSS and JavaScript. View Source on your published posts to verify block assets aren't loading on pages where those blocks aren't used. The should_load_separate_core_block_assets filter and Optimization Detective plugin help with this. SiteICO's caching layer works best when your block output is deterministic and cacheable.