Lumpsum Investment Calculator
Calculate the future value and total gain of a one-off principal invested at a fixed annual return and compounded over a number of years.
Input Data
Results
At a glance:A lumpsum investment is a single one-off amount invested at once and left to compound. The future value after n years at annual rate r is FV = P × (1 + r)^n, where P is the principal and r is the annual return as a decimal; the gain is FV − P.
Formula
Annual rate r = annual return% ÷ 100.
Future value = principal × (1 + r)^years.
Total gain = future value − principal.
$$FV = P \\left(1 + r\\right)^{t}$$How to Use
- Enter the one-off principal amount.
- Enter the expected annual return rate and the holding period in years.
- Read the future value and total gain at maturity.
FAQ
What is a lumpsum investment?
A lumpsum investment is a single one-off amount invested all at once and left to compound. The future value after n years at annual rate r is FV = P × (1 + r)^n, where P is the principal and r is the annual return as a decimal; the gain is FV − P.
How is the future value of a lumpsum calculated?
Future value = principal × (1 + annual return)^years. For example, a one-off HK$100,000 at 5% annual return for 10 years grows to about HK$162,889; the gain is the future value minus the original principal.
Should I invest a lumpsum or dollar-cost average?
A lumpsum invests immediately and captures the full compounding period, which tends to do better in rising markets; dollar-cost averaging spreads the entry and reduces timing risk. The choice depends on your risk tolerance, market view and whether you already hold the cash ready to invest.
Does a lumpsum guarantee the return shown?
No. The calculator assumes a fixed annual return for illustration; actual investments fluctuate with the market and may lose value. Treat the result as a planning estimate, not a guaranteed outcome.
How can I maximise the gain on a lumpsum?
A higher annual return and a longer holding period both increase the future value through compounding. Reinvesting any income and keeping costs and taxes low also helps the amount grow over time.
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References
Content review: Calculatorism Finance Team. Results are for reference only; please refer to the relevant authorities for the official figures.