Last updated: October 2026
What is the time value of money?
Short answer: the time value of money is the idea that money today is worth more than the same amount in the future, because money you hold now can earn interest. $1,000 invested at 5% today becomes $1,628.89 in 10 years — the calculator above runs this math for any amount, rate, and time span.
How to calculate future value
The core formula compounds a present value forward in time:
FV = PV × (1 + r)n
Take the classic example — $1,000 at 5% compounded annually for 10 years:
$1,000 × 1.0510 = $1,628.89
When you add regular contributions, each payment compounds for the time remaining after it is made. The calculator adds the future value of an annuity on top of the lump-sum growth, and the year-by-year table shows how the balance builds.
Time value of money formula explained
Compounding frequency decides how many periods fit in a year: annual (1), semi-annual (2), quarterly (4), monthly (12), or daily (365). More frequent compounding at the same nominal rate always yields a slightly higher future value, because each period's interest starts earning its own interest sooner.
Why money today is worth more than money tomorrow
Three honest reasons, no jargon:
1. It can earn. Money invested or saved at interest grows — that growth is the "price" of waiting. This is the opportunity cost of spending it now versus later.
2. Inflation eats purchasing power. If prices rise 3% a year, $100 today buys what $103 buys next year. Money held idle quietly loses value.
3. The future is uncertain. A dollar promised next year carries risk the promiser can't pay, or that you'll need it sooner. Money in hand has no such risk.
This is why lenders charge interest and investors demand returns — interest is simply compensation for the time value of money.
Frequently asked questions
What is the time value of money?
The principle that money available today is worth more than the same amount in the future, because money held today can earn interest or be invested. The calculator above shows exactly how much more, for any rate and time period.
How do I calculate future value?
Multiply the present value by one plus the periodic interest rate, raised to the number of periods: FV = PV × (1 + r)^n. For example, $1,000 at 5% compounded annually for 10 years is $1,000 × 1.05^10 = $1,628.89. The calculator above does this for any compounding frequency, with optional regular contributions.
What does compounding frequency change?
How often interest is calculated and added. Monthly compounding grows slightly faster than annual compounding at the same nominal rate, because each month's interest starts earning its own interest sooner. Try $10,000 at 8% for 20 years in the calculator: annual compounding gives $46,609.57, monthly gives $49,268.03.
What is the difference between present value and future value?
Present value is what money is worth right now; future value is what it will be worth after growing at a given interest rate for a given time. Discounting converts future value back to present value; compounding converts present value forward to future value.
Are contributions added at the start or end of each period?
At the end of each period (an ordinary annuity) — the standard assumption for savings calculators. That means a contribution does not earn interest in the same period it is made, only from the next period onward.
Is this financial advice?
No. This calculator is an educational tool that shows the math of compounding. It is not financial, investment, or tax advice — for decisions about your money, talk to a qualified professional.
Is my data private?
Completely. All calculations run locally in your browser with JavaScript — your numbers are never sent to a server, stored, or tracked in any way.
How do I calculate present value?
Present value is the future value formula run in reverse: PV = FV ÷ (1 + r)^n. If you want $1,628.89 ten years from now and can earn 5% compounded annually, you need to invest $1,628.89 ÷ 1.05^10 = $1,000 today. Investors use present value to decide whether a future payout is worth a cost today.
Can this calculator tell me how many years it takes to reach a goal?
Not directly — this calculator solves for future value only. But you can find the number of periods yourself with n = ln(FV ÷ PV) ÷ ln(1 + r). For example, turning $1,000 into $2,000 at 6%: n = ln(2) ÷ ln(1.06) ≈ 11.9 years. Try different years in the calculator above until the future value matches your target.
What is an annuity?
An annuity is a series of equal payments made at regular intervals — like a $200 monthly deposit into savings. The calculator's "regular contribution" field treats your deposits as an annuity: each contribution is grown by the compounding rate for the time remaining after it lands, then all of them are added to the lump-sum growth.
How does inflation change the answer?
The calculator shows the nominal future value, but inflation erodes purchasing power. A rough rule: real return ≈ nominal rate − inflation rate. At 7% nominal growth with 3% inflation, your real return is roughly 4%. To see today's purchasing power in the future, enter the real (inflation-adjusted) rate instead of the nominal one.
What interest rate should I use?
Use a rate that matches what the money will actually earn. Savings accounts typically pay low single digits, government bonds sit in the low-to-mid single digits, and the US stock market has averaged roughly 10% per year nominal (about 7% after inflation) over long periods. When unsure, run a conservative and an optimistic rate to see the range of outcomes.
How fast will my money double?
Use the Rule of 72: divide 72 by your annual rate to get the approximate doubling time in years. At 6%, money doubles in about 72 ÷ 6 = 12 years (check: 1.06^12 ≈ 2.01). At 9%, it doubles in about 8 years. It is an approximation, but handy for a quick sanity check.
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