Crawling December: Faceted navigation  |  Google Search Central Blog developers.google.com

Faceted navigation is a great way to help users find what they need on your site, but it can create an SEO nightmare if not implemented carefully. Why? Because it can generate a near-infinite number of URLs, leading to:

Overcrawling: Search engines waste time crawling countless URLs that aren’t valuable to search users.
Slower discovery: This overcrawling slows down the discovery of your important, new content.

In fact, faceted navigation is by far the most common source of overcrawl issues site owners report to us, and in the vast majority of the cases the issue could’ve been avoided by following some best practices. But let’s back up a little.