Introduction LinkChecker is a free, GPL licensed website validator. LinkChecker checks links in web documents or full websites. It runs on Python 2 systems, requiring Python 2.7.2 or later. Python 3 is not yet supported. Features recursive and multithreaded checking and site crawling output in colored or normal text, HTML, SQL, CSV, XML or a sitemap graph in different formats HTTP/1.1, HTTPS, FTP,