Compound Interest Calculator
Project future value from a starting balance, monthly contributions, and estimated growth rate.
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Guide
How this compound interest calculator works
This tool projects how money can grow when interest or investment returns build on top of prior growth. It combines a starting balance, recurring contributions, rate, time, and compounding frequency.
Separate contributions from growth
The result shows how much came from money added versus estimated interest or return.
Use a realistic rate
Small changes in annual return can create large differences over long periods.
Look at the time horizon
Compounding becomes more powerful as years increase because growth has more time to build on itself.
FAQs
Is this an investment guarantee?
No. It is a projection based on the rate you enter. Real investments can rise, fall, and include fees or taxes.
How are monthly contributions handled?
The calculator adds the contribution each month and applies an effective monthly growth rate based on the selected compounding frequency.
What compounding frequency should I choose?
Monthly is a common estimate for planning. Use the frequency that best matches the account or scenario you are modeling.
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