Calculator

Compound interest calculator

See how savings grow when interest is added to your balance, with optional monthly deposits.

Final balanceUSD 144,573
Money you put in
USD 58,000
Interest earned
USD 86,573
Share of the balance that is interest
59.9%
What your final balance is made of
Final balance145K
  • Money you put inUSD 58,00040%
  • Interest earnedUSD 86,57360%
How the balance growsEach bar is one year. The light part is interest.
Y1Y3Y5Y7Y9Y11Y13Y15Y17Y19
  • Money you put in
  • Interest earned

Year by year

YearTotal put inInterest earnedBalance
1USD 12,400USD 801USD 13,201
2USD 14,800USD 1,834USD 16,634
3USD 17,200USD 3,115USD 20,315
4USD 19,600USD 4,662USD 24,262
5USD 22,000USD 6,495USD 28,495
6USD 24,400USD 8,633USD 33,033
7USD 26,800USD 11,100USD 37,900
8USD 29,200USD 13,918USD 43,118
9USD 31,600USD 17,114USD 48,714
10USD 34,000USD 20,714USD 54,714
11USD 36,400USD 24,747USD 61,147
12USD 38,800USD 29,246USD 68,046
13USD 41,200USD 34,244USD 75,444
14USD 43,600USD 39,776USD 83,376
15USD 46,000USD 45,882USD 91,882
16USD 48,400USD 52,603USD 101,003
17USD 50,800USD 59,983USD 110,783
18USD 53,200USD 68,070USD 121,270
19USD 55,600USD 76,915USD 132,515
20USD 58,000USD 86,573USD 144,573
  • Deposits are added at the end of each month. Returns are not guaranteed, and taxes and fees are not included.

About this calculator

Compound interest means you earn interest on your interest. Over many years, that snowball adds far more than the money you put in yourself.

Set a starting amount, a monthly deposit, a rate and a time. The chart shows how much of your balance is your own money and how much is interest, and the table shows each year.

How it works

  • Each month your balance grows by the monthly equivalent of the yearly rate.
  • Your monthly deposit is added at the end of the month.
  • How often interest compounds changes the result a little. More often means slightly more.

Common questions

What is the compound interest formula?
Final amount = P × (1 + r/n)^(n×t), where P is the starting amount, r the yearly rate, n the times compounded a year and t the years. This calculator also adds monthly deposits.
Does compounding more often matter?
A little. Daily compounding earns slightly more than yearly at the same rate, but the rate and the time matter far more.
Is the return guaranteed?
No. Savings accounts pay a stated rate, but investments can rise and fall. Treat the result as an illustration.
Loan calculatorFind the monthly payment, total interest and yearly breakdown of any fixed rate loan.Simple interest calculatorWork out the interest on a loan or deposit when interest is not added to the balance.Savings calculatorSee how much your savings could be worth, before and after inflation.Credit card payoff calculatorFind out how long a credit card balance takes to clear and how much interest it costs.