I have been a member of CreditKarma for about six months now. I feel it is quite accurate. Once you provide them your information, they list all your accounts and then give you an update on your credit score from TransUnion(as many times you want, FREE). Not only the credit score, it provides the auto insurance score too. I was not comfortable giving out my personal info to any other sites, but they promise not to share your info to third party without your permission. As far as I am concerned, it's been all good. Ofcourse, they ask for your social security. I would suggest, if you want to sign up, to go to their website at www.creditkarma.com and not any other links like above. However, if you are skeptical, try www.quizzle.com. As far as I know, they don't require your social security number(amazing) but provide your free credit score and report every six months(not sure how they get accurate info though). Hope it helps :)