Compound Interest Calculator
See how your money grows with compound interest and regular contributions.
Final balance
$54,714.00
- Total contributed$34,000.00
- Interest earned$20,714.00
- Return60.9%
| Year | Balance |
|---|---|
| 1 | $13,201.00 |
| 2 | $16,634.00 |
| 3 | $20,315.00 |
| 4 | $24,262.00 |
| 5 | $28,495.00 |
| 6 | $33,033.00 |
| 7 | $37,900.00 |
| 8 | $43,118.00 |
| 9 | $48,714.00 |
| 10 | $54,714.00 |
Grows a lump sum (and optional regular deposits) with interest added to principal. Simple interest does not compound. A CD page is the same idea with CD labeling; 401(k) adds salary deferral and employer match.
Formula
A = P(1 + r/n)^(nt) for a lump sum. Recurring deposits use the future-value-of-annuity formula on top of that.
How to calculate
- Enter starting principal, annual rate, years, and compounding frequency.
- Add a contribution amount if you deposit on a schedule.
- Ending balance minus (principal + contributions) is interest earned.
Example
$10,000 at 7% compounded monthly for 10 years, with no extra deposits, grows to about $20,097.
Common mistake
A 7% annual rate compounded monthly is not 7%/12 as a final yield — the APY is slightly higher than 7%. This page compounds; it does not convert advertised APY unless you enter that APY as the rate.
FAQ
What is compounding?
Interest is added to principal so later interest is earned on a larger base. More frequent compounding grows slightly faster at the same nominal rate.
Is this the same as cumulative interest?
Cumulative interest is the total interest earned. This calculator shows ending balance and, from that, interest earned.