What is compounding frequency?

Compounding frequency is how often interest is added back to principal to earn further interest (typically monthly).

Are taxes and fees included?

No. Investment fees and taxes reduce real returns, so lower the rate to account for them.

What is the rule of 72?

Divide 72 by the annual return to estimate how many years it takes to double your money. At 8%, money doubles in about 9 years.

Can I model a one-time investment only?

Yes. Set the monthly deposit to 0.

Are my figures stored?

No. Calculations run in your browser.

Compound Interest Calculator

Simulate investment portfolio returns over time with initial principal, recurring monthly deposits, and annual growth rates.

Initial Principal ($)

Monthly Deposit ($)

Annual Return (%)

Years to Grow

Future Value

$113,669.42

Total Deposits

$70,000.00

$10,000 initial + $60,000 monthly

Total Interest Earned

$43,669.42

62% return on investment

Year-by-Year Balance Growth (10 Years)Show yearly breakdown

How to use Compound Interest Calculator

Enter initial principal investment.
Input recurring monthly deposit amount.
Set expected annual interest rate % and investment horizon in years.
Inspect year-by-year balance growth.

About Compound Interest Calculator

See how savings or investments grow with compound interest and regular monthly deposits. Enter a starting amount, a monthly contribution, an expected annual return, and a number of years to see the final balance and how much of it is interest.

How compounding works

Interest is added every month and then earns interest itself. Over long periods this snowballs: at 7% a year, money roughly doubles every 10 years, so most of the growth happens in the later years.

Monthly deposits are added at the end of each month. The yearly table shows the running total of what you put in and the interest earned, which makes the growth from compounding easy to see.

Choosing a realistic rate

Savings accounts pay a fixed rate, but investment returns vary from year to year. A steady rate is a simplification, so use a conservative number and treat the result as an estimate.

Inflation reduces what future money can buy. To see growth in today's money, subtract expected inflation from the return; for example, use 4% instead of 7%.

Common uses

Retirement planning: Estimate what monthly contributions could grow to by retirement.
Savings goals: Work out how long to save for a house deposit.
Comparing accounts: See the long-term difference between two interest rates.
Teaching money: Show how starting early changes the outcome.

Questions about Compound Interest Calculator

What is compounding frequency?: Compounding frequency is how often interest is added back to principal to earn further interest (typically monthly).
Are taxes and fees included?: No. Investment fees and taxes reduce real returns, so lower the rate to account for them.
What is the rule of 72?: Divide 72 by the annual return to estimate how many years it takes to double your money. At 8%, money doubles in about 9 years.
Can I model a one-time investment only?: Yes. Set the monthly deposit to 0.
Are my figures stored?: No. Calculations run in your browser.

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Comments

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