It is given in the form of a percentage. By law, loan issuers and credit card companies must clearly show customers the APR. This bottom-line number allows borrowers to easily compare rates charged by other potential lenders. For example, if a person takes out a loan with a 10% interest rate, that person would pay $10 for every $100 spent annually. Typically, a person will want a loan or credit card with the lowest APR.