Compound Interest Calculator
See how your money grows with compound interest. Compare different compounding frequencies with a year-by-year growth breakdown.
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Frequently Asked Questions
Quick answers to common questions
What is compound interest?+
Compound interest is interest calculated on both the principal and the accumulated interest from previous periods. Unlike simple interest (calculated only on principal), compound interest grows exponentially over time.
What is the compound interest formula?+
A = P(1 + r/n)^(nt), where A = final amount, P = principal, r = annual interest rate (decimal), n = number of times compounded per year, t = time in years.
How often should interest compound for maximum returns?+
More frequent compounding means higher returns. Daily compounding > monthly > quarterly > annually. However, the difference between daily and monthly compounding is relatively small for most interest rates.
What is the Rule of 72?+
Rule of 72 is a quick way to estimate how long it takes to double your money: divide 72 by the annual interest rate. At 8% p.a., your money doubles in 72/8 = 9 years.