Compound Interest Calculator

See how your money grows with the power of compounding. Works for any currency, any investment type.

How Compound Interest Works

Compound interest is often called the "eighth wonder of the world." The longer your money compounds, the faster it grows — because you earn returns on your returns.

How to Use

  1. Principal: Your starting investment amount.
  2. Rate: The annual interest or return rate.
  3. Time: How many years you leave it invested.
  4. Frequency: How often interest is compounded (monthly is most common).

The Formula

A = P × (1 + r/n)^(n×t)
  • A: Final amount
  • P: Principal
  • r: Annual interest rate (decimal)
  • n: Compounding periods per year
  • t: Time in years

Frequently Asked Questions