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.
Dead Link Checker - Check for broken links on any website
Semrush Authority Score Explained - Find out how Semrush Authority Score may help you to get better at your link building efforts when looking for quality domains, and improving your own website‘s authority.
LinkChecker - LinkChecker is a free, GPL licensed website validator.
Google SERP Snippet Optimization - SEOmofo tool replicates the appearance of a snippet in Google SERPs, which allows SEOs to optimize a page title and description for maximum click-through rate.