Currently my creditsesame faco score is about 20 points less than my creditkarma score. Back in April it was the other way around with creditsesame almost 40 points higher. Fortunately, I am in in the "Excellent" range either way, but with such large discrepancies, I was wondering which tracks more closely with the real FICO score. Anybody know?

Fluctuations like those you mention are not uncommon.
Credit Karma tracks Transunion, Credit Sesame tracks Experian, so they are different scores, aside from the fact that both are estimates of your scores. Neither are truly accurate, which is why it is valuable to occasionally get your current scores from EXP, TU and EQ.
Also, keep in mind that there are differences among EXP, TU and EQ; so even those scores will not be the same.

Neither most likely. I applied recently and was given a transunion score of 782. Last year they gave me 727. Both times my creditkarma was around 740-750. I take it with a grain of salt.

To add to unreliability of those FAKO scores, even scores based on the same credit bureau can be dozens of points apart. My scores from Credit Sesame and Quizzle (both based on Experian) are usually 25-30 points apart. The best use of these services is to make sure nothing bad has happened, not to find out my your accurate score.

Agreed. I use these mainly to make sure any activity on my report was actually initiated by me. The scores are nice to see a ballpark number of your actual score but I've learned that's it's nothing more than that.

For me Creditkarma seems to be more accurate, almost dead on, compared to Transunion score. Sesame is too high usually, 30 (!) points higher, than Experian.

Creditkarama stays pretty consistent for me but Creditsesame seems to jump all over the place each month.

Don't bother with absolute scores from the FAKO sites (CK, CS, etc). Just focus on the trend of the score over long periods and the actual data in your reports. Comparing the absolute numbers is pretty meaningless.

Neither one of those is very accurate - no idea how they come up with their numbers. Just looking at my home value - it is about $30K less than my wife's, and we happen to live in the same house - makes me wonder.

I've been wondering this for so long. My CK is always lower than CS, and a CC denial letter I got a few months ago with my score was like right in the middle between the two.

I've never gotten the same credit score from any of the places that have checked it. Credit sesame, Credit Karma, Identity guard... they've all been different. Can be very confusing/annoying.

A credit score is a proprietary equation based on credit bureau data. FICO has an equation at each bureau and the FICO score is calculated in real time based on a lender request. TU, EXP, and EQX also have their own equations which can provide a different score based on data differences between the bureaus or differences in the equations. The differences might weight a late housing payment differently than a late credit card payment, or might have a different utilization calculation. As other have said, focus on trends and ensuring that your credit report, eg the trades on it are correct .. open date, credit limit, high credit etc. Yes, FICO is used by many lenders, but it is not the only score used to determine credit worthiness. Many companies pull a FICO score, but use their own proprietary score to approve or decline an application. Its actually good to have competition in the scoring industry, and not have a single FICO score, which has a proprietary forumula for which we know general details but not specifics, as the only creditworthiness measure.

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