Loan Calculator
Work out the cost of an amortized, deferred, or bond-style loan. Enter the amount, rate, and term to see your payment, total repaid, and total interest.
Loan details
How to use this calculator
1. Pick the loan type
Choose Amortized for a normal installment loan, Deferred when the whole balance plus interest is due at the end, or Bond to find what you should pay today for a fixed amount received later.
2. Enter the amount and rate
Type the loan amount (or, for a bond, the maturity payout you'll receive) and the annual interest rate as a percentage. The calculator converts the rate to a monthly figure for you.
3. Set the term
Toggle between years and months and enter the length of the loan. Everything recalculates instantly as you type.
4. Read the results
The large figure is your headline number — the monthly payment, the lump sum due, or today's price. The two cards underneath break out the total repaid and the total interest. For a fixed monthly budget instead, try the Payment Calculator.
About loan calculations
What is the difference between amortized and deferred?
An amortized loan is repaid in equal periodic payments, each covering interest plus a slice of principal, so the balance reaches zero at the end of the term. A deferred loan is paid back as a single lump sum at maturity, with interest accruing the whole time and falling due all at once.
How is the monthly payment calculated?
For an amortized loan the payment is M = P × i / (1 − (1 + i)−n), where P is the loan amount, i is the monthly rate (annual rate divided by 12), and n is the number of months. When the rate is zero, the payment is simply the principal divided by the number of months.
How does the bond option work?
A zero-coupon bond pays a fixed amount at maturity and nothing in between. Its fair price today is that future amount discounted back at the periodic rate: price = maturity / (1 + i)n. The gap between the price and the payout is the interest you earn.