Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
SEO Site Checkup - Find comprehensive search engine optimization (SEO) tools for your site.
Custard - Custard is an interactive and intelligent search marketing agency tailored to the needs of SEO, Pay per click, and SMM campaigns.
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Searchmetrics Suite - SEO Software
Sitechecker - All-in-one SEO platform including rank tracker, website SEO audit tool and website changes monitoring. Detailed reports by 100+ parameters with how-to-fix guides.