Explore Keywords - Free keyword research tools
Screaming Frog - Screaming Frog is search engine marketing agency offering search engine optimisation and pay-per-click advertising services.
Keyword Spy - Get competitive data on other people's AdWords sem bids.
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
KeywordTool.io - KeywordTool.io is the best FREE alternative to Google Keyword Planner and Ubersuggest. It uses Google's autocomplete feature to get over 750+ long-tail keywords for any given query.
SEOmator - SEO website analysis & audit tool