<prompt> Human: Credit Karma shows my TransUnion score as 729 and my Equifax is 709. When I log into my Capital One account it also shows 729 they use TransUnion. However when I went to buy a car yesterday my TransUnion score came back 648 and my Equifax as 661. How could they be so drastically off? And Equifax came back higher than TransUnion. In what world can anyone use Credit Karma to get an idea of their credit score before applying for a loan???  <response>: Its actually not super useful for just the reason youve discovered. There a number of different FICO models offered by Fair Issac as well as FAKOs - FICO-type scores that are developed by other companies and usually only used to give consumers an approximation of your FICO. I use CreditKarma to keep an eye on my credit reports - are my accounts updating? balances correct? any fraudulent or incorrect information I need to correct? By checking in periodically I can fix problems well before they get in the way of a loan application. 