What is the Compound Interest Calculator?
See how a deposit grows with compound interest, with a choice of compounding frequency.
Enter principal, interest rate per year, time and compounded and the Compound Interest Calculator returns future value, interest earned and effective annual rate. Results update as you type, and nothing you enter leaves your device.
How it is calculated
A = P × (1 + r ÷ m)^(m × t)
r is the yearly rate as a decimal, m the compounding periods per year and t the years
How to use it
- Enter principal.
- Enter interest rate per year in %.
- Enter time in years.
- Choose compounded.
- Read future value in the results panel. It updates as you type.
- Change any value to compare scenarios, or use Share to send the result as a link.
Worked example
Common questions
What formula does the Compound Interest Calculator use?
It uses: A = P × (1 + r ÷ m)^(m × t); r is the yearly rate as a decimal, m the compounding periods per year and t the years.
What do I need to use the Compound Interest Calculator?
You need principal, interest rate per year, time and compounded. Sensible starting values are filled in so you can see how it works straight away.
Is the Compound Interest Calculator free, and is my data stored?
It is free with no sign-up. The calculation runs in your browser, so the values you enter are not sent to or stored on our server.