Finance
Compound Interest Calculator
Project how a starting balance may grow when interest is earned on both the original amount and accumulated interest.
Trust note
Calculations happen instantly in your browser. No account, API, or data submission is required.
Finance calculator
Enter your numbers
Results update as you type. Amounts are shown in USD for convenience; use the same currency for all inputs.
Result
Enter the requested values to see your estimate.
Formulas
- A = P × (1 + r / n)^(n × t)
- Interest earned = final balance - starting principal
- P is principal, r is annual rate as a decimal, n is compounding periods per year, and t is years.
Worked examples
$10,000 at 5% for 10 years
With annual compounding, the estimated balance is $16,288.95 before taxes or fees.
FAQ
What is compound interest?
Compound interest is calculated on the starting balance and on interest already added to that balance.
Does this include regular contributions?
No. This estimate uses one starting deposit and a fixed annual rate. It does not account for deposits, withdrawals, fees, taxes, or changing returns.