What are some alternatives?
When comparing Ahrefs and Keyword Spy, you can also consider the following products
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
SpyFu - SpyFu helps companies determine where the company needs to go and how to get there. Improve experience with clients by watching trends and planning new strategies.
Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.
iSpionage - AdWords competitor keywords with the click of a button and monitor competitor PPC landing pages.
Serpstat - Search analytics, Rank tracking, Backlink analysis and Site Audit tool.
RankHacker.com - The only keyword research tool that forecasts ROI & automates your content strategy.