Compound Interest Calculator interactive tool
Calculator
A monthly frequency treats this as a monthly contribution; an annual frequency treats it as an annual contribution.
Result
$32,063.02
+$10,063.02
$22,000.00
Year-by-year estimate
This table simulates the same beginning-of-period contribution and compounding assumptions used above.
| Year | Deposits | Interest | Balance |
|---|---|---|---|
| 1 | $11,200 | $544.62 | $11,744.62 |
| 2 | $12,400 | $1,178.5 | $13,578.5 |
| 3 | $13,600 | $1,906.2 | $15,506.2 |
| 4 | $14,800 | $2,732.53 | $17,532.53 |
| 5 | $16,000 | $3,662.53 | $19,662.53 |
| 6 | $17,200 | $4,701.51 | $21,901.51 |
| 7 | $18,400 | $5,855.03 | $24,255.03 |
| 8 | $19,600 | $7,128.96 | $26,728.96 |
| 9 | $20,800 | $8,529.47 | $29,329.47 |
| 10 | $22,000 | $10,063.02 | $32,063.02 |
What Is Compound Interest?
Compound interest is interest earned on the initial principal and on interest added during earlier periods. This tool estimates how a starting balance and regular contributions may grow over a chosen time period.
How the Formula Works
For a one-time deposit, the standard formula is A(1 + r/n)^(nt), where A is the starting amount, r is the annual rate as a decimal, n is the number of compounding periods per year, and t is the number of years. The regular contribution calculation is added to that result.
- Annual: one compounding period per year.
- Monthly: twelve compounding periods per year.
- Daily: 365 compounding periods per year in this estimate.
Important Assumptions
Contributions are treated as being made at the beginning of each selected compounding period. The rate stays constant, and taxes, fees, inflation, and changing market returns are not included. Use the result to compare scenarios, not as a guaranteed investment return.
How To Use the Compound Interest Calculator
- Enter your initial investment or savings amount.
- Enter the expected annual interest rate and number of years.
- Optionally add the contribution made during each compounding period.
- Choose how often interest compounds, from annually to daily.
- Review the future value and total interest earned.
Compound interest with monthly contributions
This compound interest calculator models an initial balance plus recurring deposits at an annual, semi-annual, quarterly, monthly, or daily frequency. Compare future value, total deposits, and estimated interest, then vary the rate instead of treating one savings projection as a promise.
Need the formula or convention behind this result? Read the calculator methods and assumptions.