Compound Interest Calculator
Calculates growth of money over time with compounding at any frequency
Total value after compound interest
Principal plus all monthly contributions
Growth from compound interest
Actual annual rate after compounding
Frequently Asked Questions
What is compound interest?
Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. Unlike simple interest (calculated only on the principal), compounding causes your money to grow exponentially over time. Albert Einstein reportedly called it the eighth wonder of the world.
How does compounding frequency affect returns?
More frequent compounding produces slightly higher returns. $10,000 at 6% for 10 years yields $17,908 with annual compounding, $18,061 with monthly, and $18,194 with daily. The difference is modest but adds up over long periods and with larger amounts.
What is the Rule of 72?
The Rule of 72 is a shortcut to estimate how long it takes to double your money. Divide 72 by the annual interest rate. At 6%, your money doubles in about 12 years (72/6=12). At 8%, it doubles in about 9 years. This works for any compounding investment.
Related Calculators
SEP IRA Calculator
Calculates maximum allowable SEP IRA contributions based on self-employment income
Solo 401(K) Calculator
Determines maximum Solo 401(k) contributions including both employee and employer portions
Retirement Savings Calculator
Projects how much savings will accumulate by retirement based on contributions and growth rate
Inflation Calculator
Determines purchasing power changes over time using historical CPI data