Compound Interest Calculator

See how savings and investments grow with compound interest, including regular monthly contributions.

Savers and investors projecting how their money grows over time.

How to use it

  1. Enter your starting amount

    Type the initial principal you are investing or saving.

  2. Add rate, years and contributions

    Set the annual interest rate, the number of years, and any regular monthly contribution.

  3. Choose compounding frequency

    Pick how often interest compounds, then read the final balance and total interest earned.

Why use this tool?

Compound interest is how savings and investments really grow — you earn interest on your interest, not just your original deposit. Seeing the numbers projected over years, with regular contributions, makes the long-term impact of saving clear.

Common use cases

Retirement planning

Project how a pension or long-term investment could grow over decades.

Savings goals

See how regular monthly deposits build toward a target amount.

Comparing accounts

Compare how different interest rates and compounding frequencies affect returns.

Frequently asked questions

What is the difference between simple and compound interest?

Simple interest is earned only on the principal; compound interest is earned on the principal plus previously earned interest, so it grows faster.

Does it account for monthly contributions?

Yes. Regular monthly contributions are compounded along with your starting balance.

Is this financial advice?

No. It is an estimate for illustration only and does not account for tax, fees, or inflation.

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