Interest Rate Calculator

What is APR?

The Annual Percentage Rate (APR) represents the yearly cost of borrowing, including interest and certain fees. It's expressed as a percentage of the loan amount and allows borrowers to compare different loan offers on a standardized basis.

Lenders are required by law to disclose APR, making it easier to understand the true cost of a loan beyond just the interest rate.

What is APY?

Annual Percentage Yield (APY) shows the effective annual rate when compounding is considered. It reflects how much you actually pay (or earn) over a year when interest compounds periodically.

APY = (1 + r/n)^n - 1, where r is the nominal rate and n is the number of compounding periods per year.

Rate Calculation Method

This calculator uses the Newton-Raphson method to iteratively solve for the interest rate. This numerical approach is necessary because the loan payment formula cannot be algebraically solved for the rate.

The formula: PMT = P × [r(1+r)^n] / [(1+r)^n - 1] requires iterative methods to find r.

Tips for Better Rates

• Improve your credit score before applying
• Compare offers from multiple lenders
• Consider shorter loan terms
• Make a larger down payment
• Pay points to lower your rate