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Future Value Calculator
A lump sum today, steady contributions along the way — what does it become? This future value calculator projects the ending balance and splits it into the money you put in versus the interest it earned, with result, chart and schedule updating on every slider.
See how this works on a $500-a-month savings plan — 3 real examples
Future value after 20 years
$0
Your money (put in)
$0
Interest earned
$0
Growth multiple
1.0×
Growth over time
Year-by-year accumulationDeposits, interest and end balance each year
| Year | Deposits | Interest | End balance |
|---|
How your future value is built
The starting amount grows by the standard future value formula for a lump sum:
FV = PV (1 + r/m)m·t
where PV is the present value you begin with, r is the annual rate, m the compounding periods per year and t the years. Each regular contribution is then compounded forward for its remaining time — the future value of an annuity — at the exact effective per-period rate i = (1 + r/m)m/p − 1 (or i = er/p − 1 for continuous compounding), where p is the number of contributions per year. This keeps the math exact even when the compounding and contribution frequencies differ. End-of-period contributions use the ordinary-annuity form; start-of-period contributions (an annuity due) each earn one extra compounding cycle.
The Today’s dollars view discounts the nominal future value for inflation with FVreal = FV / (1 + i)t, using your expected inflation rate. It shows what the ending balance would actually buy in present-day money — the headline figure always looks larger than its real purchasing power.
One savings plan, three honest readings
The default plan, $10,000 plus $500 a month at 7% for 20 years — read in future dollars, in today's dollars, then with deposits switched off.
The projection: $300,851 on paper
in 20 years$300,851
- Deposits total $130,000; compounding contributes $170,851 — the account earns more than it is given.
- The growth multiple reads 2.3× — each dollar in walks out as more than two.
- Right under the headline, the fine print already deflates it: about $166,574 in today’s money.
Future dollars are real dollars — they will simply be worth less by the time they arrive.
Load this example (opens in a new tab)The same balance, deflated to today
of today's purchasing power$166,574
- Nothing about the account changed — the toggle re-prices its $300,851 in current dollars.
- Twenty years of 3% inflation quietly claims $134,277 of the headline.
- Even so, the real figure still beats the $130,000 put in — the growth is genuine, only smaller.
Plans made in future dollars flatter themselves; this is the number a budget can stand on.
Load this example (opens in a new tab)The $10,000 with no help
in 20 years$40,387
- Left alone, the opening $10,000 quadruples — the steepest multiple on this page at 4.0×.
- But the dollars are small: dropping the $500 deposits costs the ending balance $260,464.
- Compounding sets the pace; the monthly habit supplies almost everything there is to compound.
A lump sum shows off the rate; contributions decide the size of the pile.
Load this example (opens in a new tab)Illustrations only, not financial advice. Your own rate, taxes and insurance will differ — check with a qualified financial advisor before acting on any of this.
Reading your future value the smart way
- Watch the split, not just the total. The bar and tiles separate the money you put in from the interest it earned — over long horizons the interest usually becomes the bigger slice.
- Contributions are the quiet workhorse. A modest deposit every month, compounded for its remaining term, often ends up outweighing a large starting lump sum.
- Time beats timing. Adding years moves the needle far more than switching between start- and end-of-period deposits, which changes the result by under a percent.
- Deflate before you dream. Flip to “Today’s dollars” so a six-figure future balance is shown as what it would truly buy — inflation quietly shrinks every projection.
- Rate is an assumption, not a promise. Model a few return rates rather than betting on one; share the link for each scenario to compare them side by side.
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Frequently asked questions
What is future value?
Future value is what a current amount — plus any contributions you keep adding — will grow to at a given rate over a set number of years. A future value calculator projects that ending balance so you can plan around it. For example, $10,000 left to grow at 7% for 20 years becomes about $40,400 before adding a single extra dollar.
What is the future value formula?
For a lump sum it is FV = PV × (1 + r)^n, where PV is today’s amount, r the periodic rate and n the number of periods. Regular deposits add the future value of an annuity on top — each contribution is compounded forward for its remaining time. The exact formula this tool uses is shown in the “How your future value is built” section below.
How do regular contributions affect future value?
A lot. Every deposit compounds for its remaining term, so consistent contributions usually end up dwarfing the starting amount. In the default scenario — $10,000 to start plus $500 a month at 7% for 20 years — the contributions and their interest add far more to the ending balance than the initial lump sum ever does.
What is the difference between an ordinary annuity and an annuity due?
With an ordinary annuity, deposits land at the end of each period; with an annuity due they land at the beginning, so each one earns one extra compounding cycle and the future value of the annuity comes out slightly higher. Use the timing toggle to compare — the gap is usually under 1% of the final balance.
How does compounding frequency change the future value?
More frequent compounding raises the effective annual yield a little, so the future value edges up as you move from annual to monthly to daily to continuous compounding. The effect is real but small: on typical inputs the difference between monthly and daily compounding is a fraction of a percent. The rate, the time horizon and how much you contribute matter far more.
Can I see the inflation-adjusted future value?
Yes. Flip the display to “Today’s dollars” and the calculator discounts the nominal future value by your expected inflation rate to show its real purchasing power. A balance of $40,400 in 20 years is only worth about $22,400 in today’s money at 3% inflation — a reminder that the headline number always looks bigger than what it will actually buy.
Disclaimer: these calculators are educational tools, not financial advice. They model your inputs with published formulas, but they cannot know your full situation — for decisions with real stakes, talk to a qualified professional. Formulas and defaults last reviewed .