Compound Interest Calculator
See how an investment grows with compound interest over time.
Compound interest earns 'interest on interest', accelerating growth the longer you stay invested.
The math behind it
A = P × (1 + r/n)^(n·t), where P is the principal, r the annual rate, n the compounding frequency per year, and t the number of years.
Worked example
$1,000 at 7% compounded monthly for 10 years → $2,009.66 ($1,009.66 interest).
FAQ
Does compounding frequency matter?
Yes — more frequent compounding yields slightly more, approaching the continuous-compounding limit.