> It's very common that credit karma will show a decent score, and then when the person applies for a loan or mortgage the score the lender uses comes up much l

> It's very common that credit karma will show a decent score, and then when the person applies for a loan or mortgage the score the lender uses comes up much lower and they get denied, and there's little they can do about it except try again later and hope the number went up. It goes beyond "there is no 'your score'" – there are absolutely credit scores that really matter, it's just the overwhelming majority of people who monitor their "score" from a free monitoring site are looking at something that may be at best a poor simulation of that score. From what I've learned from a friend who did banking software development for decades: almost every lender pulls a FICO score from all three reporting agencies, discards the high and low, and uses the middle score to make their lending decision. In some cases lenders go out of their way to avoid building in manual underwriting because the score is typically quite accurate and manual underwriting allows bias to enter the system that may open up fair lending/housing lawsuits. Credit Karma doesn't provide a FICO score. Most places that give you "free credit scores" don't. My friend says they jokingly call this a FAKO – a fake FICO. It means next to nothing because they tend to be based on an alternative model like VantageScore that isn't what lenders use to make decisions. If you want a real FICO score, you can buy them from myfico.com and get them from all three bureaus, or you can get a credit card that gives you one: all Discover cards give a monthly FICO 8 from TransUnion and AMEX gives a FICO 8 from Experian (not sure if it's all the cards, and don't go to the "give my credit score" link on their site – you have to find the link to your FICO score) His tl;dr: "a site that tells you your credit score means nothing, a site that tells you your FICO score means a great deal".