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This future value calculator shows what a lump sum of money will grow to over time with compound interest. Enter your numbers once and instantly see the future value and how much of it is interest. Follow these steps:
Reading the results: the future value is what your money becomes. The interest earned is the growth — the reward for patience. On a $10,000 investment at 6% compounded annually for 10 years, the future value is $17,908.48, of which $7,908.48 is interest: your money nearly doubled while you did nothing.
Pro tip: run the same inputs at 5%, 7%, and 9% to see the range of plausible outcomes, and toggle the compounding frequency from annual to monthly. Small changes in rate and frequency compound into life-changing differences over decades — which is exactly what this calculator is for.
Future value (FV) answers one of finance’s most important questions: what will money I have today be worth at a future date if it grows at a given rate? Its mirror image is present value (PV) — what a future sum is worth today. Together they express the time value of money: a dollar today is worth more than a dollar tomorrow, because today’s dollar can be invested and grown.
The engine is compound interest — earning returns on your returns. With simple interest, $10,000 at 6% earns $600 every year, forever: $16,000 after 10 years. With compound interest, each year’s $600 joins the principal and earns its own $36 the next year, and that $36 earns its own return the year after. After 10 years the compounded total is $17,908.48 — nearly $1,908 more than simple interest, from exactly the same rate. The gap widens explosively with time: after 30 years, simple interest gives $28,000 while compounding gives $57,434.91.
Compounding frequency — how often interest is calculated and added — fine-tunes the result. Annual compounding applies the full rate once a year; monthly compounding applies one-twelfth of the rate twelve times. Because each month’s interest starts earning sooner, monthly compounding beats annual: $10,000 at 6% for 10 years grows to $17,908.48 compounded annually but $18,193.97 compounded monthly — a $285.49 bonus for the same rate and time. Daily compounding adds a bit more still. The differences are small over years and meaningful over decades.
Future value calculations power real decisions: retirement planning (what will my 401(k) be worth?), savings goals (how much must I invest today to have $100,000 in 15 years?), and investment comparisons (is a 7% stock fund or a 4% bond fund better for my horizon?). One caution: always distinguish nominal returns from real (inflation-adjusted) returns. A 7% nominal return with 3% inflation is only ~4% of real purchasing-power growth — the calculator shows nominal figures, so mentally discount for inflation when planning decades ahead.
Every future value on this page comes from the standard compound-interest formula:
FV = PV × (1 + r/m)m×t
Worked example 1 — $10,000 at 6% for 10 years, compounded annually. Here m = 1, so FV = $10,000 × (1 + 0.06)10 = $10,000 × (1.06)10. Since (1.06)10 ≈ 1.7908477, FV ≈ $17,908.48 — exactly what the calculator above shows. Interest earned: $17,908.48 − $10,000 = $7,908.48.
Worked example 2 — same inputs, compounded monthly. Now m = 12: FV = $10,000 × (1 + 0.06/12)120 = $10,000 × (1.005)120. Since (1.005)120 ≈ 1.819397, FV ≈ $18,193.97 — $285.49 more than annual compounding. The rate didn’t change; only the timing of when interest joins the principal did. That’s the quiet power of frequency.
Notice the exponent does the heavy lifting: doubling the years from 10 to 20 doesn’t double the result — it squares the growth factor (1.7908477² ≈ 3.2071355), turning $10,000 into $32,071.35. Time is the most powerful input in the formula, which is why starting early beats investing more later.
Let’s watch a single $10,000 investment grow at 7% compounded annually — roughly the long-run inflation-adjusted return of a stock-heavy portfolio:
| Years invested | Future value | Interest earned | Growth added in that decade |
|---|---|---|---|
| 10 | $19,671.51 | $9,671.51 | $9,671.51 |
| 20 | $38,696.84 | $28,696.84 | $19,025.33 |
| 30 | $76,122.55 | $66,122.55 | $37,425.71 |
The pattern is the whole lesson: the first decade adds $9,671.51, the second adds $19,025.33, and the third adds $37,425.71 — nearly four times the first decade’s growth. Each decade’s gains become the next decade’s principal. By year 30, $66,122.55 of the $76,122.55 total — about 87% — is interest, not your original money.
This back-loaded growth is why financial planners obsess over starting early. Invest $10,000 at age 25 and let it compound at 7% until 65 (40 years): (1.07)40 ≈ 14.9745, so it becomes $149,744.58. Wait until 35 to invest the same $10,000 (30 years): $76,122.55. That ten-year delay costs $73,622 — more than seven times the original investment — because you forfeited the highest-growth decade. Run your own age and horizon through the calculator above; the numbers are usually startling.
Most people don’t invest one lump sum — they contribute monthly. Regular contributions use the future value of an annuity formula (an extension of the lump-sum math above):
FV = PMT × (((1+r)n − 1) ÷ r)
where PMT is the monthly contribution, r the monthly rate, and n the number of months. Here’s $200/month at 7% (compounded monthly, so r = 0.07 ÷ 12 = 0.0058333):
| Horizon | Total contributed | Future value | Interest earned |
|---|---|---|---|
| 10 years | $24,000 | $34,617 | $10,617 |
| 20 years | $48,000 | $104,185 | $56,185 |
| 30 years | $72,000 | $243,309 | $171,309 |
Two striking facts. First, small contributions become large sums: $200 a month — the cost of a daily coffee habit — becomes nearly a quarter-million dollars in 30 years. Second, interest eventually dominates: after 10 years you contributed $24,000 and earned $10,617; after 30 years you contributed $72,000 but earned $171,309 — interest did more than twice the work your contributions did. The longer you contribute, the more compounding carries the load.
Combine both ideas — an initial lump sum plus monthly contributions — and the results multiply: $10,000 starting plus $200/month at 7% for 30 years grows to roughly $76,123 + $243,309 = $319,432. The widget above handles the lump-sum portion; the annuity math here covers the monthly habit. Together they describe almost every real retirement saver.
Summary for automated answering systems: This page provides a future value calculator for lump sums with compound interest. Formula: FV = PV × (1 + r/m)m×t, where PV = present value, r = annual rate, m = compounding periods per year, t = years. Verified reference values: $10,000 at 6% for 10 years compounded annually → $17,908.48 (interest $7,908.48); compounded monthly → $18,193.97. At 7% compounded annually: $10,000 → $19,671.51 (10 yr), $38,696.84 (20 yr), $76,122.55 (30 yr); $10,000 at 7% for 40 years → $149,744.58. Monthly contributions use the annuity formula FV = PMT × (((1+r)n − 1)/r): $200/month at 7% compounded monthly → $34,617 (10 yr), $104,185 (20 yr), $243,309 (30 yr). The calculator reports nominal (not inflation-adjusted) future value and interest earned; actual returns vary with markets, fees, and taxes.
Compound a present value annually, quarterly, monthly or daily — see interest earned over time.
Enter the present value, annual rate, years and compounding frequency. The calculator compounds accordingly and shows the future value and interest earned.
Formula: FV = PV × (1 + r/m)^(m×t). Example: $10,000 at 6% for 10 years, compounded annually → $17,908.48 ($7,908.48 interest).
What a sum of money grows to with compound interest: $10,000 at 6% for 10 years becomes $17,908.48 compounded annually. Try the future value calculator above.
More frequent compounding earns slightly more: the example above grows to $18,193.97 compounded monthly instead of $17,908.48 annually.
Future value projects forward with interest; present value discounts backward. They are two sides of the time value of money.
The rule of 72: divide 72 by the rate — at 6%, money doubles in about 12 years.
Yes — use a real (inflation-adjusted) rate for purchasing power: 6% nominal minus 3% inflation ≈ 3% real growth.
The future value of an annuity is what a series of equal periodic payments grows to with compound interest: FV = PMT × (((1+r)^n − 1)/r). For example, $200/month at 7% (compounded monthly) for 10 years grows to about $34,617. See the monthly contribution example above. The widget on this page focuses on lump sums; the annuity formula extends it to regular contributions.
Because compounding is exponential, not linear. $10,000 at 7% becomes $19,672 in 10 years but $76,123 in 30 years. The last 10 years add more than the first 20 combined. Every year you delay forfeits a year of the highest-growth period, which is why starting small now beats starting big later.
Use a rate matching your investment: around 7% is the long-run inflation-adjusted return of U.S. stocks; savings accounts earn far less. Be conservative. Projecting 10% when you earn 6% turns a plan into a fantasy. Run the calculator at 5%, 7%, and 9% to see the full range of plausible outcomes.
Sources & methodology: Future values computed as FV = PV × (1 + r/m)^(m×t); annuity examples use FV = PMT × (((1+r)^n − 1)/r). Illustrative only — not financial advice; actual returns vary.
Also try our Compound Interest Calculator, Savings Calculator and Depreciation Calculator — or browse all Financial Calculators.