რთული სარგებლის კალკულატორი
გამოთვალეთ ძირითადი თანხისა და რეგულარული ყოველთვიური შენატანების მომავალი ღირებულება, შენატანებისა და სარგებლის წლიური განაწილებით.
შემოწმებულია OmniCalc-ის გუნდის მიერმეთოდი დამოწმებულია 2026-07-01
Added at the end of each month
$37,405.09
Future value $37,405.09- Total contributed
- $22,000.00
- Total interest
- $15,405.09
- Future value
- $37,405.09
Year-by-year growth
| Year | Balance | Contributed | Interest |
|---|---|---|---|
| 1 | $11,962.16 | $11,200.00 | $762.16 |
| 2 | $14,066.16 | $12,400.00 | $1,666.16 |
| 3 | $16,322.27 | $13,600.00 | $2,722.27 |
| 4 | $18,741.46 | $14,800.00 | $3,941.46 |
| 5 | $21,335.54 | $16,000.00 | $5,335.54 |
| 6 | $24,117.15 | $17,200.00 | $6,917.15 |
| 7 | $27,099.84 | $18,400.00 | $8,699.84 |
| 8 | $30,298.15 | $19,600.00 | $10,698.15 |
| 9 | $33,727.66 | $20,800.00 | $12,927.66 |
| 10 | $37,405.09 | $22,000.00 | $15,405.09 |
Estimate only — it assumes a fixed rate and excludes taxes, fees and inflation. Not financial advice.
How to use the compound interest calculator
- 1Enter your starting amount and, if you save regularly, a monthly deposit.
- 2Set the annual rate, how many yearsyou’ll stay invested, and how often interest compounds (monthly is typical).
- 3Read the projected balance, then check the year-by-year table to see how much is your own money versus interest earned.
- 4Nudge the rate or the monthly deposit to see how much either one moves the finish line.
The compound interest formula
A = P(1 + r/n)^(nt)
A is the future value, P the starting principal, r the annual rate as a decimal, n the number of compounding periods per year, and t the number of years. The rate is treated as a nominal annual rate, so the periodic rate is r/n.
Monthly contributions are added at the end of each month (an ordinary annuity) and then compound alongside the principal, so the balance shown already blends both the lump sum and your regular deposits.
Worked example
Suppose you start with $10,000 at a 7% nominal annual rate, compounded monthly, and add $100 at the end of every month for 10 years.
- The periodic rate is 7% ÷ 12 ≈ 0.583% per month, applied over 120 months (10 × 12).
- The $10,000 lump sum alone grows to about $20,097 using 10,000 × (1 + 0.07/12)^(12 × 10).
- The 120 monthly $100 deposits add roughly $17,300 more once their own compounding is included.
- Total future value is about $37,400, of which $22,000 is money you contributed and the rest is interest.
Time is the biggest lever
Because interest earns interest, the years matter more than the rate. Starting a decade earlier usually beats chasing a slightly higher return, and a modest monthly deposit left alone can overtake a larger lump sum given enough time. Try pushing the years up before you reach for a higher rate — the curve steepens toward the end.
Frequently asked questions
What is compound interest?
Compound interest is interest earned on both your original amount and on the interest already added. Because each period's growth is itself earning interest, the balance grows faster and faster over time — the classic 'interest on interest' effect.
How often should interest compound?
More frequent compounding gives a slightly higher balance for the same nominal rate: daily beats monthly beats quarterly beats yearly. The difference is small at ordinary rates but widens over long horizons. This calculator lets you compare yearly, quarterly, monthly and daily.
What is the rule of 72?
The rule of 72 estimates how many years it takes money to double: divide 72 by the annual rate. At 7% a lump sum doubles in roughly 72 ÷ 7 ≈ 10.3 years. It is a quick mental shortcut, not an exact figure — use the calculator for the precise result.
Are taxes included?
No. This tool shows gross growth before any tax, fees or inflation. Real after-tax returns depend on your account type, jurisdiction and marginal rate, so treat the future value as an upper-bound estimate.
Formulas follow standard time-value-of-money conventions (future value and ordinary-annuity). Estimates are informational only and not financial advice. Last reviewed 2026-07-01.