A credit score is a number between 300 and 850 that lenders use to determine whether to extend you credit, the amount of credit you qualify for, and even the terms (interest rate, loan amount, repayment schedule). Generally, scores over 700 are considered excellent while scores below 600 may need some work.
The score is determined by the three leading credit bureaus: TransUnion, Equifax and Experian. Your creditors — the companies, lenders, and organizations that lend you money and extend credit to you — report information to them such as your credit limit and whether you pay on time. Each agency keeps its own records so your score can vary from bureau to bureau. For a mortgage loan, generally the middle score is used.