Compound Interest Calculator
Work out compound interest from a starting amount, rate and time, with monthly or yearly contributions. See the final balance, interest, yearly table and chart.
How to calculate compound interest
- Enter the starting amount, the yearly interest rate and how long you save.
- Choose how often interest compounds (monthly, quarterly, yearly…) and any amount you add each month or year.
- The final balance, total interest, chart and yearly table appear right below.
Frequently asked questions
With compound interest, each period's interest is added to the balance, so the next period earns interest on it too. The longer the time, the bigger the gap with simple interest.
The more often interest compounds (monthly rather than yearly), the slightly higher the final balance at the same yearly rate. "Continuous" is the upper limit, from the formula e to the power of rate times time.
A contribution at the start of a period earns interest during that period, so the total ends up a little higher than with contributions at the end.
It is an estimate from the formula. Banks may round daily, pay a lower rate on early withdrawals or deduct tax and fees, so what you receive can differ a little.
It is completely free and needs no sign-up.
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