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Compound Interest Calculator

Calculate how your savings grow with compound interest. Choose your compounding frequency and see your final balance instantly.

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How to use

  1. Enter your initial deposit (the amount you are starting with).
  2. Enter the annual interest rate as a percentage.
  3. Choose how often interest compounds — annually, quarterly, monthly, or daily.
  4. Enter the duration in years.
  5. Your final balance and total interest earned appear instantly.

About this tool

Compound interest is the process of earning interest on both your original deposit and the interest already accumulated. Unlike simple interest — which is calculated only on the principal — compound interest grows exponentially over time, which is why time is the most powerful variable in long-term savings. The frequency of compounding matters: a rate compounded monthly produces a higher return than the same rate compounded annually. This calculator shows your final balance and the total interest earned separately, so you can see how much of your end sum was your own money and how much was growth. All results are for illustrative purposes; actual savings returns depend on your product terms.