Loan Calculator
Calculate a loan's monthly payment or its term, plus total interest and total cost, from amount, rate, and the value you know.
How loan payments are calculated
M = P · r · (1 + r)ⁿ / ((1 + r)ⁿ − 1)
This is the standard amortizing-loan formula, where P is the loan amount, r is the monthly interest rate (annual rate ÷ 12 ÷ 100), and n is the number of monthly payments. Switch the mode to solve for the monthly payment (from a term) or for the term (from a monthly payment). Rearranged, the term is n = −ln(1 − P·r/M) / ln(1 + r).
Worked example
A 20 000 loan at 6% annual interest over 5 years (60 payments): the monthly payment is about 386.66, the total repaid is about 23 199.36, and the total interest is about 3 199.36.
When solving for the term, the monthly payment must be larger than the monthly interest on the balance — otherwise the loan can never be repaid. This is an estimate for a fixed-rate amortizing loan; real loans may add fees or use a different compounding basis.