Use google adwords external tool - where you can put your website and the tool will scan your whole website and then will give the list of all keywords used in website. There will be complete details of your website with Keyword Global monthly traffic and Local monthly traffic with Competition value. Then you can check everything related to your website keywords. Hope so you like this tool !
Google adwords is the best tool for finding keywords. But create keywords manually instead of using any tool. As find such words which highly entered by people for their query in your field. Set those words as your keywords and this way your keyword be highly searched by people and you can get position for your keywords.
Google adwords does offer the best responses when searching for things but i am in the search for a couple more.
If you are talking about how to find out right keywords for a website then Google adwords does it or if you want that how to know the ranking keys of a website you just go for webmaster tool whereas you can find out the those keys who are actually ranking or visitors are coming through which keys.
