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Compound Interest Calculator

Estimate future value, total contributions, interest earned, and year-by-year growth with periodic compounding.

View all calculatorsBuild a full amortization schedule

Your estimated results

The sample values are calculated automatically. Enter your own information for a new estimate.

These calculators provide mathematical estimates for education and planning. Loan agreements, lender practices, fees, taxes, payment dates, and rounding can change actual results.

How the calculation works

Compound Interest Calculator explained

Compound interest earns interest on both the original amount and prior interest. More frequent compounding slightly increases the effective annual return when the nominal rate is unchanged.

Recurring contributions can have a larger effect than changing the compounding frequency because each deposit also has time to earn interest.

The calculator assumes a constant rate and contribution. It does not include taxes, investment fees, or market fluctuations.

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Need a complete loan schedule?

Use the free online amortization calculator to view every payment, annual totals, charts, extra payments, rate changes, and balloon dates.

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Amortization Pro lets you edit individual payment rows, save and retrieve loans, export CSV files, and print complete reports. One-time price: $25.

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Frequently asked questions

What is the difference between nominal and effective annual rate?

The nominal rate is the stated annual rate. The effective rate reflects the effect of compounding during the year.

When are recurring contributions added?

This calculator adds each contribution at the end of the compounding period.

Why does daily compounding show many contributions?

The contribution field applies once per compounding period. For daily compounding, use $0 unless you truly intend a daily contribution.