Compound Interest Calculator
Calculate how your money grows with compound interest for any principal, rate, and tenure. Enter your details below to see the maturity amount and total interest earned.
What is Compound Interest?
Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. Unlike simple interest, which is charged only on the principal, compound interest causes your money to grow exponentially over time — a phenomenon often called the "eighth wonder of the world."
The formula used is A = P(1 + r/n)^(nt), where P is the principal, r is the annual rate, n is the number of compounding periods per year, and t is the time in years. The more frequently interest is compounded, the greater the final amount — which is why monthly compounding yields more than annual compounding at the same nominal rate.
Compound interest works in your favour when you are an investor (in FDs, PPF, or mutual funds) but against you when you carry debt (credit cards, personal loans). Starting early and reinvesting returns are the two most powerful levers to maximise the compounding effect.
This calculator is for educational and illustrative purposes only. Actual returns may vary based on the institution and specific product terms.