SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Whatsmyserp - Powerful Rank & Serp Tracking. Completely Free.
SEOmator - SEO website analysis & audit tool
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
Panguin Tool by Barracuda Digital - See your website's Google organic visit data overlaid with Google's major algorithm updates and changes to easily identify the impact on your website. Technology by Barracuda Digital.
Ahrefs - Ahrefs is a toolset for SEO and marketing. We have tools for backlink research, organic traffic research, keyword research, content marketing & more. Give Ahrefs a try!