SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Screaming Frog - Screaming Frog is search engine marketing agency offering search engine optimisation and pay-per-click advertising services.
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
SEOmator - SEO website analysis & audit tool
SEOquake - SEOquake provides a browser extension to conduct on-page SEO audit.
Rank Tracker - Rank Tracker is an SEO tool for tracking and improving keyword rankings across multiple websites and search engines.