Crawl budget signals

Google's crawl-budget guide targets sites with 1 million+ unique pages changing about weekly, 10,000+ pages changing daily, or many URLs in 'Discovered – currently not indexed' (rough estimates, not exact thresholds); others need only an up-to-date sitemap. Budget per hostname is crawl capacity (rises with stable, fast responses; falls with slow responses, 5xx and 429) times crawl demand (perceived inventory, popularity, staleness). Google advises consolidating duplicates, robots.txt (not noindex) for URLs that shouldn't be crawled, 404/410 for removed pages, eliminating soft 404s, fresh sitemaps with lastmod, avoiding long redirect chains, faster pages and 304 support.