Compound Interest Calculator
See how your money grows with compound interest. Set principal, rate, compounding frequency and years — get the final balance, total interest and a year-by-year growth chart. Free, instant.
How to use this tool
- Enter starting amount, annual interest rate, compounding frequency and years in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your final balance and the full breakdown beneath it.
Compound interest earns interest on your interest, so balances grow faster the longer you stay invested. This calculator compounds your starting amount at the rate and frequency you choose and charts the year-by-year balance.
Formula: A = P(1 + r/n)nt, where P is the principal, r the annual rate, n the compounding periods per year and t the years.
Frequently asked questions
- What does compounding frequency change?
- More frequent compounding (e.g. daily vs annually) earns slightly more, because interest is added — and starts earning — sooner.
- Does this include monthly contributions?
- No — this is for a single lump sum. Use the Investment Growth Calculator to add regular monthly contributions.