The good news is, there are number of free keyword search tools available to help you like wordstream free keyword tool, Google Keyword planner, Ahref etc. From all these Google keyword planner is the best one and also free to use. You can take help from any of these.
Tool like RankActive could generate a list of the keywords any website is already ranked for as well as help you find similar, ranked, suggested keywords using its Keyword Finder tool. At the same time you can check rankings in real time and have multiple websites withing a single account.
rankstat.io is one more tool to find what keywords a website is ranked for – it is absolutely free
keywordfox.com is also a free tool for keyword research
There are many SEO tools available to check the website keywords. The list of best keywords checker tools is Google Keyword Planner, uber suggest, Semrush. LongTailpro and Ahref etc. The Google keyword planner is one of the top keyword checkers tools. It’s a Google product and free of cost tools for checking the keyword.