GetReviewed.org - Get Your Product featured on Authority Product Review Blogs! Connect with bloggers, get reviews!
Dead Link Checker - Check for broken links on any website
PrePostSEO Domain Authority Checker - DA PA Checker (Domain Authority Checker) is developed to check bulk DA PA with spam score & IP Address for up to 500 URLs at once.
BrokenLinkCheck - Free Broken Link Checker / Online Dead Link Checking Tool - find bad hyperlinks
Ahrefs Backlink Checker - With the world's biggest index of live backlinks (over 15 trillion), Ahrefs Backlink Checker will show you the most complete backlink profile for any website.
LinkChecker - LinkChecker is a free, GPL licensed website validator.