Drupal Facets

I need to...	Guide	Summary
Understand what Facets does and decide between Facets/BEF/core filters	Overview	Use Facets when you need faceted search navigation with result counts, narrowing behavior, and hierarchical filtering — and you are using Search API. Use Better Exposed Filters when you want enhanced widgets for any Views exposed form…
Install Facets and set up Search API	Installation & Setup	Use this guide when setting up Facets on a Drupal site with Search API.
Understand facet sources and how they connect to Views	Facet Sources	Use this guide when you need to understand how facets connect to your search backend and Views displays, or when a facet source is not appearing.
Create and configure a facet entity	Facet Configuration	Use this guide when creating or configuring a facet entity — selecting the source, field, widget, operators, and processors.
Understand the processing pipeline (pre_query → build)	Processing Pipeline	Use this guide when you need to understand how facets process data from query to rendering, or when debugging unexpected facet behavior.
Choose the right widget (links, checkbox, dropdown)	Widgets	Use this guide when choosing how facet results should be rendered to the user.
Use the range slider sub-module	Range Slider Widget	Use this guide when you have numeric facets (price, rating, year) and want a visual slider interface.
Add a searchbox to filter facet items	Searchbox Widget	Use this guide when a facet has many items and you want users to type to filter the visible options client-side.
Transform values (IDs to labels, dates, booleans)	Value Transformation Processors	Use this guide when facet raw values need to be converted to human-readable labels — entity IDs to names, boolean values to Yes/No, dates to formatted strings.
Filter and limit results (count limit, hide non-narrowing)	Result Filtering Processors	Use this guide when you need to control which facet items are displayed — hiding items with low counts, removing specific values, or showing only narrowing results.
Sort facet results (by count, display value, weight)	Sort Processors	Use this guide when you need to control the order of facet result items.
Build hierarchical facets (taxonomy, dates)	Hierarchy	Use this guide when faceting on hierarchical data — taxonomy vocabularies with parent-child relationships or date facets with year → month → day grouping.
Understand URL parameter handling	URL Processors	Use this guide when you need to understand how facet selections are represented in URLs, or when customizing URL behavior.
Know how query types work (string, date, range)	Query Types	Use this guide when you need to understand how facet selections are translated into search backend queries, or when facets are not filtering correctly for a field type.
Use Facets as Views exposed filters with BEF	Facets Exposed Filters	Use facets_exposed_filters when you want facets integrated into the Views exposed form — the recommended approach in Facets 3.x. This gives you native Views AJAX, BEF widget support, and simpler configuration.
Display active facet selections with summary	Facets Summary	Use this guide when you want to display active facet selections as removable breadcrumbs — "Color: Blue (x) | Size: Large (x) | Reset all".
Expose facets via REST API	Facets REST	Use this guide when building a headless or decoupled frontend and you need facet data (values, counts, active states, URLs) in API responses.
Prevent bot and AI scraper crawling of facet URLs	SEO & Bot Protection	Use this guide when deploying any site with Facets. Facets have ZERO built-in SEO or bot protection.
Handle facet URL canonicalization	Canonical URLs & Duplicate Content	Use this guide when faceted pages create duplicate content issues — the same results appearing at multiple URLs due to different facet parameter ordering or pagination combinations.
Override facet templates in my theme	Theming & Templates	Use this guide when customizing the HTML output of facets in your theme.
Subscribe to facet events	Events	Use this guide when you need to hook into the facets processing pipeline without creating a full custom processor — for example, modifying URL formats, overriding active filter detection, or adjusting cache metadata.
Understand facet caching	Caching	Use this guide when you need to understand or debug facet caching behavior, or when facets show stale data or wrong results after caching.
Create custom processors, widgets, or query types	Custom Plugin Development	Use this guide when you need a custom processor, widget, query type, or URL processor that doesn't exist in the built-in set.
Use the facets_pretty_paths contrib module	Pretty Paths	Use this guide when you want cleaner facet URLs — /search/color/blue/size/large instead of ?f[0]=color:blue&f[1]=size:large.
Debug common facet problems	Common Mistakes	Use this guide when debugging facet issues or reviewing a faceted search implementation before going to production.