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.
RobinGupta Bulk Domain Authority Checker - Free tool to bulk check domain authority, Page Authority, Spam score & IP Address.
Backlinks by Neil Patel - A backlinks research tool for competitive intelligence
SmallSEOTools Google Cache Checker - Google Cache checker is an online tool to view cached pages, Enter any website URL to find when was the last time your web page was cached.
SEMScoop - Find and analyze easy to rank long-tail keywords with free SEMScoop Keyword Difficulty Tool, Start using them for SEO, PPC, content creation and all your marketing activities
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.