Semrush offers a complete suite of tools for keyword analysis, and much more. If tasked with discovering the value, or usage of keywords, it truly rules to the roost. It’s able to give accurate costings for keywords should Adwords be your things also.
I’ve used this tool to gauge the costs for clients in different sectors. It’s proved perfect when showing a client the numbers behind their sectors associated keywords
A research tool for startups, webmasters who need stats for clients, or marketeers
You will lose hours in the sheer amount of data you never knew you needed