See how a starting balance and a regular monthly contribution grow over time ā and exactly how much of the final total is your own money versus interest earned. Compounding is what turns steady saving into real wealth. Nothing is sent to a server.
Compounding is the engine; a plan tells you when it gets you to financial independence. The complete Glidepath planner adds inflation, taxes in 43 countries, pensions, Monte Carlo stress-testing and your whole life plan ā free and private.
Open the full FIRE planner āCompound interest is interest earned on your interest. Each period, the growth is added to your balance, so next period you earn returns on a bigger pile ā and the one after that, bigger still. Over a few years the effect is modest; over decades it's enormous, which is why starting early beats saving more later. Albert Einstein reportedly called it the eighth wonder of the world.
For a starting amount that grows plus regular deposits, the future value is two pieces ā the lump sum compounding, and an annuity of your contributions:
Final = PĀ·(1+i)N + CĀ·[ ((1+i)N ā 1) Ć· i ]
where P is your starting amount, C each contribution, i the rate per compounding period, and N the number of periods. The coloured bar above splits your final balance into what you put in (starting amount + contributions) versus the interest compounding earned you ā the gap is the whole point of investing early.
This calculator uses a fixed rate in nominal terms. Real returns vary year to year, and inflation erodes future money ā the full Glidepath planner handles both.
Related: Savings rate calculator Ā· Coast FIRE Ā· How long will my money last?
Estimates only, not financial advice. Assumes a constant rate and steady contributions in nominal terms; real returns vary and inflation reduces future buying power. Your inputs stay in your browser ā nothing is sent to a server. Ā· Full planner Ā· All calculators Ā· Savings rate Ā· Coast FIRE Ā· How it works Ā· Feedback