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Compound Interest Calculator

Calculate compound interest on your savings or investments. See how your money grows with different compounding frequencies.

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Disclaimer

This calculator provides estimates for general information purposes only. Results are based on standard formulas and may not reflect your individual circumstances. Always consult a qualified professional for advice specific to your situation.

Frequently Asked Questions

How does compound interest work?
Compound interest earns interest on both your initial amount and previously earned interest. For example, $10,000 at 7% compounds to $19,672 in 10 years — nearly double. With monthly contributions of $200, it grows to $54,832. Time is the biggest factor.
What is the Rule of 72?
Divide 72 by your annual return rate to estimate how many years it takes to double your money. At 7% return, your money doubles in approximately 72 ÷ 7 = 10.3 years.

What is Compound Interest?

Compound interest is when you earn interest on both your initial investment and on the interest that has already been added — effectively earning interest on your interest.

How this calculator works

This calculator applies the compound interest formula with regular contributions. You choose the compounding frequency (daily, monthly, quarterly, or annually) which determines how often earned interest is added to the balance and starts earning its own interest. More frequent compounding means slightly higher returns. The stacked area chart shows the split between your total deposits and the interest earned, making the power of compounding visually clear — especially over longer time periods.

All calculations are performed in your browser — your data never leaves your device. Results are for general guidance only and should not be considered professional financial advice.

Built and maintained by Konstantin Iakovlev. Data sourced from the ATO and official Australian government sources.