Google announced the guidelines on Search Central in its `Crawling December` series. Most of the information is in the original post, with some important updates.
Here’s Google’s announcement on LinkedIn:
Google recommends
Gary Illyes said in his `Crawling December’ post that site owners should prevent faceted navigation from being crawled to avoid search engines from indexing it if they don’t need it.
They should also follow Google’s guidelines and best practices to complete mobile numbers list sustain efficient URL spaces and avoid overloading their site’s crawl budget.
Gary wrote:
“If you don’t need the faceted navigation URLs potentially indexed, prevent crawling these URLs.”
“If you need the faceted navigation URLs potentially indexed, ensure that the URLs follow our best practices outlined in the following section. Keep in mind that crawling faceted URLs tend to cost sites large amounts of computing resources due to the sheer amount of URLs and operations needed to render those pages.”