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An annuity is simply a series of equal payments made at regular intervals — and its future value is the total those payments grow to once compound interest has done its work. The calculator above tells you exactly where a savings habit leads: enter what you can set aside each period, and it compounds every single payment from the day it goes in, then adds everything up into one future-value figure plus a clean split between what you contributed and what compounding earned for you.
Getting your answer takes under a minute:
Pro tip: test the two levers that matter most — time and amount. First model your current plan, then add five or ten years to see what starting earlier (or retiring later) is worth, then try raising the payment by $50. Most people are stunned to find that extra years beat extra dollars, which is precisely why this calculator shows contributions and interest separately.
The future value of an annuity answers one of the most practical questions in personal finance: if I set aside the same amount on a regular schedule and it grows at a steady rate, how much will I have at the end? The annuity itself is the stream of equal, evenly spaced payments — your monthly 401(k) contribution, a quarterly college-fund deposit, or yearly premium payments. The future value (FV) is what that stream is worth on the date of the final payment, after every deposit has earned compound interest for however long it was invested.
A few core terms make everything else click. Compounding means each period’s growth is calculated on the previous balance plus all earlier growth — interest earning interest, the engine behind every figure on this page. The payment frequency is how often deposits occur: monthly (12 per year), quarterly (4), or yearly (1). The per-period interest rate is the annual rate divided by the number of periods per year — a 7% annual rate means about 0.5833% per month. An ordinary annuity assumes each payment lands at the end of its period (the standard assumption in finance, and the one this calculator and its formula use). An annuity due assumes payments land at the beginning of each period, giving every deposit one extra period of growth.
The single most important insight is that earlier payments earn more. A dollar deposited in year 1 of a 30-year plan compounds 30 times; a dollar deposited in year 29 compounds only twice. That is why two savers can contribute identical totals and end up with wildly different balances: the one who started earlier let time do the heavy lifting. Concretely, $200 deposited monthly at 7% grows each payment independently — the first $200 compounds for the full 120 months of a 10-year plan while the last $200 barely compounds at all — and the calculator’s total of $34,616.96 reflects exactly that per-payment math.
This concept shows up everywhere once you recognize it. Retirement saving is the classic case: decades of small automatic contributions compounding into a large nest egg. Sinking funds work the same way — setting aside $150 a month for a future car purchase or roof replacement. Education savings, emergency-fund building, and even business capital-expenditure planning all reduce to the same question this calculator answers: what does a disciplined stream of deposits become?
The future value of an ordinary annuity comes from this standard formula:
FV = PMT × (((1 + r)n − 1) ÷ r)
Here PMT is the payment per period, r is the per-period interest rate (annual rate ÷ periods per year), and n is the total number of payments (years × periods per year). The bracketed factor — sometimes called the FV annuity factor — is just the sum of each payment’s individual growth: the first payment compounds n−1 times, the next n−2 times, and so on down to the last payment, which earns no interest. The formula adds that whole geometric series in one step.
Worked example 1. You invest $200 per month at 7% annual return for 10 years. Convert to per-period terms: r = 0.07 ÷ 12 = 0.0058333, and n = 10 × 12 = 120 payments. Compute (1 + r)n = (1.0058333)120 ≈ 2.00966. The annuity factor is (2.00966 − 1) ÷ 0.0058333 = 1.00966 ÷ 0.0058333 ≈ 173.085. Multiply by the payment: FV = $200 × 173.085 ≈ $34,616.96 — exactly what the calculator above shows. Your contributions total $200 × 120 = $24,000, so compound growth contributed $10,616.96, nearly 44% extra on top of what you put in.
Worked example 2. You deposit $100 per quarter at 5% annual return for 15 years. Quarterly terms: r = 0.05 ÷ 4 = 0.0125, and n = 15 × 4 = 60 payments. Compute (1.0125)60 ≈ 2.10718. The factor is (2.10718 − 1) ÷ 0.0125 = 1.10718 ÷ 0.0125 ≈ 88.574. Then FV = $100 × 88.574 ≈ $8,857.44. You contributed $100 × 60 = $6,000, and compounding added $2,857.44. Notice how the lower rate and quarterly frequency produce a smaller growth multiple than the first example — both levers visible in a single number.
Two useful variations: for an annuity due (payments at the beginning of each period), multiply the ordinary-annuity result by (1 + r), since every payment gets one extra compounding period. And to convert between frequencies fairly, always divide the annual rate by the periods per year rather than using the annual rate directly — a common error that wildly overstates growth.
Now the scenario that makes the concept unforgettable. Suppose at age 35 you automate a $500 monthly investment earning an average 7% annual return until age 65 — 30 years of steady deposits.
In per-period terms: r = 0.07 ÷ 12 = 0.0058333, n = 360 payments, and (1.0058333)360 ≈ 8.11653. The annuity factor is (8.11653 − 1) ÷ 0.0058333 ≈ 1,219.98, so FV = $500 × 1,219.98 ≈ $609,990. Your total contributions are $500 × 360 = $180,000 — which means compound growth contributed roughly $429,990. Read that again: growth supplied more than twice what you deposited. In the final decade alone, the account earns more from compounding than the entire first decade’s contributions.
This is why financial planners obsess over automating contributions rather than timing markets. You did not need investment genius — just $500 a month, a diversified portfolio averaging 7%, and the patience to leave it alone for 30 years. Raise the payment to $750 and the future value scales linearly to about $914,985; raise the return to 8% and compounding’s curvature pushes it far higher. But the cheapest improvement of all is time, which brings us to the next example.
Compare two savers who both invest $200 per month at 7%. Saver A starts at 45 and invests for 10 years; Saver B starts at 35 and invests for 20 years.
Saver B contributed exactly twice as much — but ended up with three times the money, because the first decade’s payments compounded for an extra ten years. The extra $24,000 Saver B deposited in years 1–10 did not just add $24,000; at 7% it roughly tripled on its own. This asymmetry is the entire argument for starting retirement saving in your twenties and thirties even with small amounts: a 25-year-old’s dollar has 40 compounding periods ahead of it, while a 55-year-old’s dollar has only 10.
The practical takeaway: if you are young, prioritize starting now with whatever you can afford — even $100 a month — over waiting until you can afford $500. And if you are catching up later in life, the math says you must lean harder on the payment amount, since time can no longer do the work for you. Either way, run your exact numbers in the calculator above before deciding.
1. Plugging the annual rate in as the per-period rate. The formula needs r per payment period. Using 7% (0.07) instead of 0.58333% (0.0058333) for monthly payments inflates the result astronomically — a $200/month, 10-year plan would wrongly show over $138,000 instead of $34,616.96. Always divide the annual rate by the number of payments per year.
2. Mixing up ordinary annuities and annuities due. The standard formula assumes end-of-period payments. If you actually deposit at the start of each month, every payment earns one extra period of growth, and the true future value is higher by a factor of (1 + r) — about 0.58% more per month at 7%. Small per period, but it compounds across decades.
3. Ignoring inflation, taxes, and fees. A 7% nominal return with 3% inflation is roughly a 4% real return — your $609,990 retirement figure buys far less than it sounds. Investment fees of 1% per year can erase nearly a quarter of a 30-year balance. Model with real (after-inflation) returns for honest planning.
4. Underestimating the cost of waiting. Delaying saving by five years does not cost you five years of deposits — it costs you the most valuable five years, the earliest ones with the longest compounding runway. As the example above showed, a decade’s delay can cut your final balance by two-thirds even if you later contribute the same monthly amount.
5. Comparing rates without matching compounding frequency. A 7% rate compounded monthly (effective 7.23%) beats 7% compounded yearly. When comparing accounts or projections, convert everything to the same per-period basis — or better, to effective annual rates — before declaring a winner.
For a different view of the same math, try the Future Value of $1 Annuity Table Creator, which builds the full factor table period by period — handy for double-checking hand calculations or classroom work. And the complete Financial Calculators collection covers the companion questions: what a lump sum grows to, what loan payments cost, and how much house you can afford.
Page summary: This page provides a future value of annuity calculator. Inputs: payment per period (dollars), annual rate (percent), years, payment frequency (monthly, quarterly, yearly). Outputs: future value of annuity, total contributions, interest earned, number and size of payments. Method: each payment compounded individually from its deposit date at the per-period rate r = annual ÷ periods-per-year; equivalent to FV = PMT × (((1+r)^n − 1) ÷ r) for an ordinary annuity. Reference figures: $200/month at 7% for 10 years → FV $34,616.96 (contributions $24,000, interest $10,616.96, 120 payments); $500/month at 7% for 30 years → FV ≈ $609,990 (contributions $180,000). Scope: fixed rate, end-of-period payments; excludes inflation, taxes, and fees.
Sources: standard time-value-of-money mathematics as published in finance textbooks and by the U.S. Securities and Exchange Commission’s investor education materials (investor.gov). Worked-example figures were computed with the formulas above and cross-checked against the calculator widget on this page. Figures rounded to the nearest cent; actual investment results vary with market performance, fees, and timing.
Grow regular payments with compound interest — see future value and interest earned.
About $34,616.96 — your $24,000 of payments plus $10,616.96 of compound interest. Try the calculator above.
The total your stream of equal payments grows to, with each payment compounding from the day it goes in.
Monthly wins slightly: payments go in sooner and start compounding earlier. The difference is small but real.
FV = PMT × (((1+r)^n − 1) ÷ r), with r the per-period rate and n the total number of payments.
Both — but early payments benefit most, since they compound the longest. Starting early beats contributing more later.
Also try our Future Value of $1 Annuity Table Creator.