Future Value Calculator
See what a starting amount and regular contributions could grow to, and how much of that is interest.
Principal and contributions
Combine a lump sum today with regular deposits and let compounding work on both.
A projection, not a promise
Real returns vary year to year — use this to compare scenarios, not to guarantee an outcome.
What is future value?
What money today becomes tomorrow
Future value is what an amount of money will be worth at a later date, given an interest or growth rate and how often it compounds. It is one of the core ideas in finance: money has time value, so a sum invested today grows as it earns a return on both the original principal and the interest already added. As references such as Investopedia explain, the future value of a series of regular contributions builds on the same idea, adding the growth of every deposit you make along the way.
The calculator combines two pieces: the growth of your starting amount and the growth of your contributions.
FV = PV × (1 + r)ⁿ + PMT × [((1 + r)ⁿ − 1) / r]Here PV is the present value (your starting amount), PMT is the contribution each period, r is the periodic rate (the annual rate divided by the number of periods per year), and n is the total number of periods. The first term grows your lump sum; the second is the future value of an ordinary annuity — every contribution earning a return from the period it is made until the end. Choosing monthly, quarterly, or annual compounding sets both how often interest is added and how often you contribute.
You start with 10,000, add 200 a month, expect a 7% annual return, and invest for 10 years with monthly compounding.
Find the periodic rate
7% ÷ 12 = about 0.583% per month, over 120 months.Grow the starting amount
10,000 × (1.00583)^120 ≈ 20,100.Grow the contributions
200 × [((1.00583)^120 − 1) ÷ 0.00583] ≈ 34,600.Add them up
About 54,700 — of which 34,000 is money you paid in and roughly 20,700 is interest.
Three levers shape the future value, and time is the most powerful of them.
Time compounds
The longer the horizon, the more interest earns interest — the curve steepens sharply over decades.
Rate matters most later
A higher return barely changes the first years but dominates the final value over long periods.
Contributions build the base
Regular deposits add a steady stream of new principal for compounding to work on.
The split between contributions and interest is revealing: early on, most of the balance is money you paid in, but given enough time the interest can exceed your total contributions. That crossover is why starting early matters far more than contributing a little extra later.
The future value is the projected balance at the end of the term. The total contributions show how much of that is your own money — the starting amount plus every deposit — and the interest earned is everything above that, the reward for letting it compound. Comparing the two tells you how hard your money is working: a long horizon and a steady rate can turn modest contributions into a balance where interest is the largest part. Treat the figure as a projection under a constant rate, and rerun it with a lower rate to see a more conservative case.
The maths is exact; the future is not.
Projections are not guarantees
This calculator assumes a single, constant rate of return and contributions made at the end of each period. Real investments fluctuate, can lose value, and rarely return the same amount every year, so the result is a smoothed projection rather than a forecast. It also ignores inflation, taxes, and fees, all of which reduce what your future value is actually worth or what you keep. Use it to compare scenarios and understand compounding, and consult a qualified financial advisor before making investment decisions.