What is Keywords Everywhere?
Keywords Everywhere is a freemium chrome extension and firefox add-on.
The free version has the following features
The paid version has the following features
When do I need to pay?
You need to purchase credits only if you want to see the monthly search volume, CPC, and competition numbers.
Every time the extension gets volume data for a single keyword, it uses up one of your credits. Here is an article with more details on how credits work.
If you only care about the keywords shown in the Related & PASF widgets, and the YouTube insights, then you can use the extension for free without any need to pay.
How do I setup Keywords Everywhere and start using it?
Make sure you go through the following instructions