Compound Interest Calculator

Growth over time, with your choice of compounding frequency.

Calculate compound interest growth on a principal amount over time, with a choice of compounding frequency, and see how much more it earns compared to simple interest.

Frequently asked questions

What formula does this use?

A = P(1 + r/n)^(nt), where P is the principal, r is the annual interest rate, n is how many times per year interest compounds, and t is the time in years.

Does compounding frequency really matter?

Yes, though the effect is usually modest — the same rate compounded monthly earns slightly more than compounded annually, since interest starts earning its own interest sooner.