Compound Interest Calculator
Calculate future value, contributions, and compound-interest growth from an initial amount, monthly deposits, rate, and term.
This selection sets the currency unit only; amounts are not converted using exchange rates.
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Frequently Asked Questions
How Compound Interest Works
Compound interest means you earn interest on both your principal and previously earned interest. This "interest on interest" effect accelerates growth dramatically over time — especially with regular monthly contributions.
The Rule of 72
A quick way to estimate how long it takes to double your money: divide 72 by the annual interest rate. At 7% per year, your money doubles roughly every 10 years (72 ÷ 7 ≈ 10.3 years).