APR vs Interest Rate Comparator

APR vs interest rate: why the difference matters

When comparing loan offers, the stated interest rate is only part of the picture. The Annual Percentage Rate (APR) is the more complete measure because it incorporates both the interest rate and the upfront fees charged by the lender, expressed as an annualised percentage of the loan amount. Two loans with identical interest rates can have materially different APRs if one charges significant origination fees, discount points, or broker fees. The APR allows you to compare the true cost of competing loan offers on a standardised basis.

The mechanics of APR are based on the concept of effective yield. When you pay upfront fees on a loan, you receive less money than the loan principal suggests (your net proceeds are the principal minus the fees), but you still repay the full principal amount plus interest. This means the lender earns a higher return than the stated interest rate implies. The APR calculation finds the interest rate that, applied to the net proceeds, produces the same monthly payment as the stated rate applied to the full principal. For a $20,000 loan at 6.5% with $500 in fees over 60 months, the monthly payment is fixed at $391.32, but the effective APR on the $19,500 in net proceeds is approximately 7.1%.

The difference between stated rate and APR grows with the size of the fees relative to the loan amount and shrinks with longer loan terms. A $500 fee on a $20,000 loan represents 2.5% of the principal, which has a meaningful impact on a 12-month loan but a much smaller annualised impact on a 60-month loan. This is why short-term loans with fixed origination fees often have dramatically higher APRs than their stated rates suggest, while 30-year mortgages show a much smaller gap between rate and APR. When comparing loans of different terms, the APR comparison is more meaningful than the monthly payment comparison alone.

What fees are included in APR?

Under the US Truth in Lending Act (TILA), lenders are required to disclose APR on most consumer loans, and the calculation must include origination fees, discount points, broker fees, and certain prepaid interest. However, not all fees are required to be included: appraisal fees, title insurance, credit report fees, and some third-party charges may be excluded depending on the loan type. This means two lenders disclosing the same APR may have different total costs if they differ in which fees they include in the APR calculation. Always read the Loan Estimate and Closing Disclosure carefully for mortgage loans, and the loan agreement for personal loans, to identify all costs.

Using APR to compare loan offers

The correct way to use APR for loan comparison is to compare loans of the same type and term. APR is most reliable when comparing fixed-rate, same-term loans from different lenders. When comparing a 36-month personal loan to a 60-month personal loan, the lower APR on the 60-month loan does not mean it is cheaper overall, because you pay interest for longer. Total interest paid is a better metric for comparing loans of different terms, since it directly tells you how much extra you spend to borrow the money. Use this calculator to see both APR and total interest paid so you can make a complete comparison.