What is compound interest?
Compound interest is interest on your interest. You earn interest on your original money, and then next period you earn interest on that slightly bigger amount too. Over years, this snowball effect means your savings grow faster and faster — which is why starting early matters so much.
Why monthly deposits are powerful
Adding even a small amount every month gives compounding more fuel. A modest starting amount plus a steady monthly deposit, left for many years, often grows into far more than you'd expect — most of the final total can end up being interest, not your own deposits.
A simple example
Save a starting amount, add a little monthly, leave it for 10–20 years at a reasonable rate, and the interest earned can rival or exceed everything you put in. Time is the real ingredient. Use the calculator above to try your own numbers.