First off Ck uses Vantage scoring NOT FICO scoring which what lenders use. The most economical way to get all three scores is Credit Check Total for $1 trial. Just be sure to cancel before the 7 days are up.
Ck is a good tool to keep up with alerts and inquiries and new accounts in near real time, but those scores are often as much as 100 points different than your true scores that are used to make credit decisions.
Yes. I believe they are using FICO 8, not sure about the version. But it will give you a true score. you are also able to get a free annual report of all three bureaus if you are troubled by your score so that you can see what is truly in there.