Present & Future Value

A dollar today isn't a dollar in ten years. Price the difference.

Amount = money you invest today.

How to use time-value math

  1. Pick a direction. Future value grows money forward; present value discounts it back.
  2. Enter amount, rate, and years. The amount is today's money (FV mode) or the future sum (PV mode).
  3. Set compounding and contributions. Monthly compounding with a monthly contribution is the classic savings plan.
  4. Press Calculate. The answer, what you put in, and what compounding contributed.

Frequently asked questions

What is the time value of money?

Money today can earn returns, so it's worth more than the same sum later. Future value grows it forward with interest; present value discounts a future sum back at a required return.

How does compounding frequency matter?

Interest-on-interest accrues each period, so monthly compounding slightly beats annual at the same nominal rate. The effect is small next to the rate itself.

What's the formula?

FV = PV×(1+r)^n for a lump sum; contributions add PMT×(((1+r)^n−1)/r). Present value runs the same math backwards.

What discount rate should I use for PV?

Your required return — often a safe rate for valuing guaranteed cash, or a higher hurdle for risky ones. The answer is very sensitive to it.

Why does the growth column dwarf my contributions?

Compounding is exponential: over decades, returns on returns snowball past what you put in. Starting early beats contributing more later.

Is this financial advice?

No. Planning estimates only — real investing carries risk this math ignores.

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