Annuity Calculator

An ordinary annuity pays at the end of each period, while an annuity due pays at the start. Because every payment in an annuity due is invested or discounted one period earlier, both its present value and future value are higher by a factor of (1 + r).

For an ordinary annuity, PV = PMT * (1 - (1 + r)^-n) / r, where PMT is the payment, r is the rate per period as a decimal and n is the number of periods. For an annuity due the result is multiplied by (1 + r).

For an ordinary annuity, FV = PMT * ((1 + r)^n - 1) / r. An annuity due multiplies that by (1 + r). When the rate is zero there is no growth or discounting, so both present and future value equal the payment times the number of periods.

Use the rate that matches your period. If payments are monthly, enter the monthly rate, which is roughly the annual rate divided by 12. If they are annual, enter the annual rate. The number of periods must use the same unit.

Yes. The calculation runs entirely in your browser. Your payment, rate and period figures are never sent to a server or stored, so nothing leaves your device.