Screaming Frog SEO Spider
Desktop crawler for technical audits
The SEO Spider is a desktop crawler that fetches a site the way a search engine would and reports what it finds: response codes, redirect chains, titles and meta descriptions, headings, canonicals, hreflang, structured data, images and internal link structure. The free version crawls a limited number of URLs per crawl, which covers small sites completely; the paid licence removes the limit and unlocks scheduling, JavaScript rendering, custom extraction and saved configurations.
Because it runs on your own machine, large crawls depend on your memory and disk rather than a subscription tier. It connects to Search Console, Analytics and PageSpeed Insights so crawl data can be joined with real performance data, which is what turns a list of URLs into a prioritised list of problems.