Faceted navigation is a filtering system that allows a visitor to narrow down a product listing by parameters. From a search engine's point of view, however, it is an address generator: with ten filters with several values each, hundreds of thousands to millions of combinations are created, the vast majority of which contain nearly identical content or an empty listing. Without rules, crawling is spent on them and the index fills up with worthless pages. The solution rests on deciding which combinations have their own demand – typically brand, size, colour or purpose – and treating those as fully fledged landing pages with their own description. The remaining combinations are excluded from indexing or not made accessible to the robot at all. A stable order of parameters in the URL also helps, so that the same combination does not arise in ten different variants.
See also: Index bloat, Crawl budget, Product variants.
