Crawl budget is the number of pages a search engine crawler is willing and able to go through on your website within a given period. It is determined by two factors: how much the server can handle without slowing down, and how worthwhile it is for the crawler to crawl the site, that is, how often something of value changes on it. Small websites do not need to worry about this, but for e-shops and portals with tens of thousands of URLs it becomes a limiting factor. The budget is most often spent on things that should not be in the index: endless filter combinations, search results, pagination, test URLs, and chains of redirects. It can be redirected back by blocking unnecessary URLs, speeding up the server response, removing dead links, and keeping a clean sitemap that contains only URLs that should be indexed.
See also: Index bloat, Faceted navigation, Redirect chains.
