Reviewed November 2026 · Estimate only, not financial advice.
An annuity is a series of equal payments — a retirement payout, a structured settlement, or a monthly savings habit. Enter the monthly payment, the annual rate and the years, and see what the whole stream is worth, both at the end and today.
How This Annuity Calculator Works
An ordinary annuity pays at the end of each month. Its future value is the sum of every payment grown by compound interest to the final date; its present value is the sum of every payment discounted back to today. The monthly rate is the annual rate ÷ 12, and the number of payments is years × 12.
FV = PMT × ((1 + r)n − 1) ÷ r · PV = PMT × (1 − (1 + r)−n) ÷ r
PMT = monthly payment, r = monthly rate, n = number of payments.
Worked example: $200 a month at 6% annual interest for 20 years (240 payments). Future value = $92,408.18. Present value = $27,916.15. Total paid in = $200 × 240 = $48,000, so the growth is $92,408.18 − $48,000 = $44,408.18.
Practical tips
Present value is the price of the stream.If someone offered to buy your $200-a-month, 20-year stream, $27,916 is roughly its fair value at 6% — offers far below that are a bad deal.
End-of-month vs start-of-month matters a little.Payments at the start of each month (an annuity due) earn one extra month of interest each — about 0.5% more future value here. This calculator uses end-of-month payments, the common convention.
The rate drives the present value.At 4% the same stream is worth $32,663 today; at 8% only $23,850. The discount rate you pick is the whole negotiation.
Compare with a lump sum.Would you rather have $27,916 now or $200 a month for 20 years? At 6% they are equal — your choice depends on whether you can really earn 6%.
Frequently Asked Questions
What is an annuity?
A series of equal payments made at regular intervals — for example a monthly retirement payout, a structured settlement, or a fixed monthly savings contribution.
What is the difference between future value and present value of an annuity?
Future value is what the stream is worth at the end of the payment period, with every payment grown by interest. Present value is what the stream is worth today, with every payment discounted back.
What is an ordinary annuity vs an annuity due?
An ordinary annuity pays at the end of each period; an annuity due pays at the start. This calculator uses ordinary (end-of-month) payments, the most common convention.
How does the rate affect the result?
A higher rate grows the future value (more interest earned) but shrinks the present value (future payments are discounted harder).
Can I use this for a mortgage or loan?
The same math underlies loan payments: a loan is an annuity whose present value equals the amount borrowed. The Mortgage Calculator shows it in loan form.
Is this financial advice?
No. This is a planning estimate only, not financial advice.
