Compound Interest Calculator
Grow savings with compounding and monthly contributions.
Tool inputs stay in your browser · optional AI search sends your query
How to use it (step by step)
- 1Fill in the boxes: “Starting amount”, “Monthly contribution”, “Annual return”, “Years”, “Compounding”. Example numbers are already there so you can see how it works; replace them with yours.
- 2The result updates instantly as you type (on a phone it is below the boxes).
- 3The bold line is the main answer. Tap Copy next to any value to copy it.
Words to know
- Interest
- The extra money you pay for borrowing, like a rental fee for using someone else’s money.
- Compound interest
- Interest that also earns interest over time, so savings (or debt) grow faster and faster.
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