Compound Interest Calculator
Project your investment growth with regular contributions. See the year-by-year breakdown of contributions vs. interest earned.
Final Balance
$0
- Total Contributed $0
- Total Interest Earned $0
How compound interest works
Compound interest pays interest on your interest. Each period, your earnings are added back to the principal, and the next period's interest is calculated on the new, larger balance. The longer you let it run, the more powerfully it compounds.
A = P(1 + r/n)nt
Where P is principal, r is annual rate, n is compounds per year, and t is years. With regular monthly contributions, we add the contribution to the balance each month and let it compound from there.
The chart shows your projected balance year-by-year. The shaded area represents how much of your final balance came from contributions vs. compounded interest.
Show the math
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