See how your money grows when interest earns interest. This compound interest calculator shows the future value of a starting amount plus regular monthly contributions, with daily, monthly, quarterly or yearly compounding, and a year-by-year growth table.
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The compound interest formula
For a single amount, A = P × (1 + r ÷ n)n × t, where P is the starting amount, r the yearly rate, n the number of compounding periods per year and t the number of years. Monthly contributions are added at the end of each month and earn interest from then on.
Frequently asked questions
What is compound interest?
Compound interest is interest calculated on both your original money and the interest it has already earned. Over long periods it grows much faster than simple interest, which is paid only on the original amount.
What is the rule of 72?
Divide 72 by the yearly interest rate to estimate how many years it takes to double your money. At 8% a year, money doubles in about 9 years.
Results are estimates and assume a steady interest rate. Related: Investment (SIP) calculator · Savings goal calculator