Definition

Faceted navigation is a common website feature that lets visitors change how a list of items is filtered or sorted — by attributes like size, colour, brand or price — usually by adding parameters to the URL.

Because each combination of filters can produce a distinct URL, faceted navigation can create a very large or effectively infinite set of URLs for crawlers to discover. Google's guidance is that this can lead to over-crawling and slower discovery of the pages a site actually wants indexed, and it suggests controlling crawler access to filter URLs — for example with robots.txt — unless a particular filtered view needs to be indexed. When faceted URLs are crawlable, Google recommends standard parameter separators and returning proper status codes for empty results.

Examples

• E-commerce filters

  A clothing store lets shoppers filter by size and colour. Selecting 'medium' and 'blue' produces /shirts?size=medium&colour=blue — one of thousands of filter combinations a crawler could reach.

• Controlling crawl

  To stop Googlebot crawling every filter combination, a store disallows its filter parameters in robots.txt and keeps its clean category pages crawlable.

Sources

• Google Search Central — Managing crawling of faceted navigation URLs

Related terms

• Crawl Budget
  The number of URLs a search engine crawler will fetch and the rate at which it fetches them on a given site.
• URL Parameters
  Key-value pairs appended to a URL after a question mark, used to filter, sort, track or otherwise vary the response without changing the path.
• Canonical Tag
  An HTML element that tells search engines which URL is the master copy when the same or similar content exists at multiple addresses.

Where QueryCatch uses this

• SEO Audit
• Sitemap Optimisation