See what your money becomes: a starting amount, regular contributions, and time. The chart splits every year into what you put in versus what compounding earned — the part that sneaks up on people.
Compound interest is the quiet trick behind almost every retirement account: your money earns interest, then the interest earns interest, and after enough years the growth dwarfs the deposits. It's also famously hard to feel intuitively — which is why this calculator draws it. Enter a starting amount, what you'll add regularly, a rate, and a horizon, and the stacked chart shows each year split into what you contributed versus what compounding earned. Watching the teal band overtake the blue one is the whole lesson.
The calculator converts your rate and compounding choice into an effective annual rate
(EAR = (1 + r/n)n − 1), then simulates growth
period by period, crediting contributions at the end of each period — the standard convention. The year-by-year
table shows the running balance, total contributed, and total interest, so you can check any year against your
own statements or another calculator.
How much you have and how much you save is nobody's business but yours. Every calculation here runs in your browser — the numbers you type are never uploaded or stored on a server. Your inputs are remembered locally on your own device so the page opens where you left off.
Enter your starting amount, the monthly contribution, the expected annual return, and the years. The calculator compounds it all correctly and separates what you deposited from what growth added, on a chart and a year-by-year table.
Set the horizon and watch: the striking part is how the growth curve steepens in the later years, because returns start earning returns. It is the visual argument for starting early, and the year-by-year table makes it concrete.
It is how often earned interest starts earning its own interest: daily, monthly, quarterly, or annually. More frequent compounding grows slightly faster; the calculator supports the full range so you can match your account's terms.
Yes. Set an optional yearly increase to your contribution (matching salary growth) and the projection reflects a plan that grows with your income instead of freezing at today's number.
That is your call, not ours, but common planning ranges run from conservative bond-like rates to historical stock-market averages. Run the calculator at a few rates and plan against the range rather than a single guess.