Future Value Calculator
What a lump sum and regular contributions grow to at a given rate — and how much of the result is your own money.
Future value compounds a present amount forward: FV = PV(1+r)ⁿ.
How the future value calculator works
Future value compounds a present amount forward: FV = PV(1+r)ⁿ. Add regular contributions and each one compounds for however long it has left, which the annuity term handles in one step.
The row worth reading is the split between what you put in and what the growth added. Early on, almost all of the balance is your own contributions; the crossover — where growth exceeds everything you have paid in — typically arrives somewhere between year 15 and year 25 at ordinary rates, and that crossover is the entire argument for starting early.
Contributions are treated as arriving at the end of each period. Paying at the start instead adds one period of growth to every contribution, which is shown as a separate row.
Formula: FV = PV(1+r)ⁿ + PMT·[((1+r)ⁿ − 1)/r]
Worked examples
| Inputs | Future value | Note |
|---|---|---|
| 10,000 plus 500 a month for 20 years at 7% | £292,465.03 | about 288,000 |
| No starting balance | £253,768.19 | contributions alone |
| A lump sum left alone | £76,122.55 | compounding with no additions |
FAQFrequently asked questions
What is future value?
What an amount today, plus any contributions, grows to by a future date at a given rate.
Does this account for inflation?
The headline figure does not; the "today's money" row discounts it at 2.5% a year so you can see the difference.
Are contributions at the start or end of the period?
End, which is the standard annuity convention. The separate row shows the start-of-period figure, which is always a little higher.
Why does the growth share matter?
Because it shows when compounding takes over. Early on the balance is mostly your own money; the crossover is what long horizons buy you.
Is a 7% return realistic?
It is a common long-run assumption for a diversified share portfolio before fees and tax. Actual returns vary enormously year to year, and the order they arrive in matters as much as the average.
Where these figures come from
- CFA Institute — Quantitative Methods: The Time Value of Money — the discounting, annuity and IRR conventions used here
- US Federal Reserve — Regulation Z (Truth in Lending), APR calculation — why APR includes fees where a nominal rate does not
- MoneyHelper (UK Government-backed) — the UK's free money guidance service
Last checked: September 2026. These are the standard textbook formulas; the conventions named are those of the CFA Institute curriculum and ISO 80000 usage.