Is this compound interest calculator free?

Yes, completely free with no account, subscription, or hidden fee required.

Does it upload my financial data to a server?

No. All calculations run 100% in your browser — your numbers never leave your device.

Does it work offline or without an internet connection?

Yes. Once the page is loaded, no network connection is needed. It works fully offline.

Which compounding frequencies are supported?

Daily (365×/year), monthly (12×), quarterly (4×), and annually (1×) compounding are all supported.

Can I include regular monthly savings contributions?

Yes. Enter any monthly contribution amount and the calculator factors it into each period's balance and the year-by-year breakdown.

Is the rate I enter nominal or effective?

It is the nominal annual rate, which is then compounded at the frequency you choose. That is why the same 7% produces a slightly different total at annual, quarterly, monthly and daily compounding. Quoted savings and loan rates are normally nominal, so entering the advertised figure directly is usually correct.

Does the result account for inflation or tax?

No. The figure is a nominal projection of the arithmetic only. Real purchasing power grows more slowly than the number shown, and interest is usually taxable, so treat the output as the gross before either. A rough way to see the real growth is to enter your rate minus expected inflation instead.

What is the rule of 72?

Divide 72 by the annual rate to estimate how many years it takes to double: at 7% that is about ten years, at 9% about eight. It is a mental shortcut rather than the exact figure this calculator produces, but it is close enough at ordinary rates to sanity-check a result before trusting it.

📈 Compound Interest Calculator

Instantly calculate compound interest and project your investment's future value — including monthly contributions — free and entirely in your browser with no login or file upload required.

Inputs

Principal

Annual Rate (%)

Years

Compounding

Monthly Contribution

Currency

Future Value

—

Total Contributions

—

Total Interest Earned

—

Private by design. This tool runs entirely in your browser — nothing you enter is uploaded or stored, and it works offline.

About

This tool computes compound interest using daily, monthly, quarterly, or annual compounding, and generates a full year-by-year breakdown of your balance, contributions, and interest earned — all exportable as CSV. Because every calculation runs locally in your browser, your financial figures never leave your device and no account is needed.

How to use

Enter your starting principal (e.g. $10,000).
Set the annual interest rate and investment period in years.
Choose a compounding frequency: daily, monthly, quarterly, or annually.
Optionally add a monthly contribution to model regular savings.
View the future value, total interest earned, and year-by-year table — then copy or download the results as CSV.

FAQ

Is this compound interest calculator free?: Yes, completely free with no account, subscription, or hidden fee required.
Does it upload my financial data to a server?: No. All calculations run 100% in your browser — your numbers never leave your device.
Does it work offline or without an internet connection?: Yes. Once the page is loaded, no network connection is needed. It works fully offline.
Which compounding frequencies are supported?: Daily (365×/year), monthly (12×), quarterly (4×), and annually (1×) compounding are all supported.
Can I include regular monthly savings contributions?: Yes. Enter any monthly contribution amount and the calculator factors it into each period's balance and the year-by-year breakdown.
Is the rate I enter nominal or effective?: It is the nominal annual rate, which is then compounded at the frequency you choose. That is why the same 7% produces a slightly different total at annual, quarterly, monthly and daily compounding. Quoted savings and loan rates are normally nominal, so entering the advertised figure directly is usually correct.
Does the result account for inflation or tax?: No. The figure is a nominal projection of the arithmetic only. Real purchasing power grows more slowly than the number shown, and interest is usually taxable, so treat the output as the gross before either. A rough way to see the real growth is to enter your rate minus expected inflation instead.
What is the rule of 72?: Divide 72 by the annual rate to estimate how many years it takes to double: at 7% that is about ten years, at 9% about eight. It is a mental shortcut rather than the exact figure this calculator produces, but it is close enough at ordinary rates to sanity-check a result before trusting it.