Compound Interest Calculator

See how your money grows over time with compound interest. Enter your principal, rate, and time period below.

Principal ($):

Annual Rate (%):

Years:

Compounds per year:

How Compound Interest Works

Formula: A = P(1 + r/n)^(nt), where P = principal, r = annual rate, n = compounds per year, t = years. Interest is earned on both the principal and previously earned interest.

Frequently Asked Questions

What is compound interest?
Compound interest is interest calculated on the initial principal and also on accumulated interest from previous periods.

How often should interest compound?
More frequent compounding (daily or monthly) yields slightly more than annual compounding.

What is the Rule of 72?
Divide 72 by the annual interest rate to estimate how many years it takes to double your money.