SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Site Rank Data - View historical rank information of websites via time series charts.
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
HypeStat - HypeStat is free statistics and analytics service, where you can find information about every website.
Website Checker Tech - WebsiteChecker.Tech is SaaS tool that detects SEO and availability issues of your website, making it easier for you to fix them.
Q-Stats - Get free marketing insights for every question on Quora.