FICO Score is the standard 300-850 credit-scoring model produced by Fair Isaac Corporation. It's the score model used by ~90% of US lenders for actual lending decisions. Five factors drive the score: payment history (35%), amounts owed/utilization (30%), credit history length (15%), credit mix (10%), new credit (10%).
FICO scores range from 300 to 850. Industry conventions: 800+ exceptional, 740-799 very good, 670-739 good, 580-669 fair, below 580 poor. Different lenders use different cutoffs, but the categorization tracks. FICO score variants matter for specific products. FICO 8 is the general consumer score most credit-monitoring services show. FICO 2 / 4 / 5 (older models) are used for mortgages by Fannie Mae / Freddie Mac. FICO Auto Score 8 is the auto-loan variant — weights auto-loan payment history more heavily. FICO Bankcard Score 8 is the credit-card variant. FICO vs VantageScore: VantageScore is a competing model from the three credit bureaus. Used by Credit Karma, Credit Sesame, Capital One CreditWise. Tracks closely with FICO but differs by 20-50 points typically. When applying for a loan, the LENDER pulls FICO — VantageScore is an estimate. FICO scores update when the bureaus refresh underlying data (typically monthly). Significant credit events (new accounts, payment history changes, utilization changes) can move the score 20-50 points in a single update. The CFPB's consumer guide on credit reports and scores (https://www.consumerfinance.gov/consumer-tools/credit-reports-and-scores/) explains how FICO scores are calculated and how to access your report. The FTC's guide on the Fair Credit Reporting Act (https://www.ftc.gov/legal-library/browse/statutes/fair-credit-reporting-act) covers your rights to dispute inaccurate data that affects your FICO score.
Different scoring models from different companies. FICO is used by ~90% of US lenders for actual lending decisions. VantageScore is used by Credit Karma, Credit Sesame, and several free credit-monitoring services. The two scores typically differ by 20-50 points; FICO is the one that matters for loan applications.
Free options: Experian's free tier shows FICO Score 8. Discover Credit Scorecard (free for non-cardmembers too) shows FICO. Many credit card issuers (Chase, Amex, Capital One) show a free FICO on monthly statements. For all 3 bureaus' official FICO scores, myFICO ($19.95/month) is the direct source.