SEO Analyzer By Neil Patel - A free SEO analyzer for your site
Serpstat - Search analytics, Rank tracking, Backlink analysis and Site Audit tool.
Serpstat Website SEO Checker - Check your website's SEO, analyze competitors and keywords
Ubersuggest - Want more traffic? Ubersuggest shows you how to win the game of SEO. Just type in a domain or a keyword to get started.
Nightwatch - A forward-thinking SEO tracking and website performance tool.
SE Ranking - All-in-One cloud-based SEO software for agencies, marketing teams and webmasters