Credit Karma does not give you a real FICO score. It does provide a estimate of what your score could be. I would be careful, I have seen people who had 100 pt differences btwn their FICO and Credit Karma.

Best bet is myfico.com to see your TransUnion and Equifax and to get free your annual credit report. Its the best of the not so great options you have.

If you want to know more you can check out this page Know Your Credit Score if you want more info about credit scores.