The lump sum investment formula tells you what a single, one-time investment will be worth after a number of years. It is the standard compound interest formula, and once you understand it you can check any calculator, bank quote or fund projection yourself.
The formula
FV = future value · P = amount invested · r = yearly return as a decimal (12% = 0.12) · t = number of years
If interest is compounded more than once a year, use FV = P × (1 + r/n)n×t, where n is the number of compounding periods per year (4 for quarterly, 12 for monthly).
Worked example step by step
Say you invest 1,00,000 for 10 years at 12% a year.
- Convert the rate: 12% = 0.12, so 1 + r = 1.12.
- Raise it to the number of years: 1.1210 = 3.1058.
- Multiply by the amount: 1,00,000 × 3.1058 = 3,10,585.
Your money roughly triples. The gain of 2,10,585 is the return. You can try your own numbers instantly with the lump sum calculator.
More examples
| Investment | Return | Years | Future value |
|---|---|---|---|
| 1,00,000 | 12% | 10 | 3,10,585 |
| 10,00,000 | 12% | 10 | 31,05,848 |
| 10,00,000 | 10% | 20 | 67,27,500 |
| 5,00,000 | 12% | 15 | 27,36,783 |
Does compounding frequency matter?
Yes, a little. The same 1,00,000 at 12% for 10 years becomes:
- 3,10,585 with yearly compounding,
- 3,26,204 with quarterly compounding (like most bank FDs),
- 3,30,039 with monthly compounding.
Mutual fund returns are quoted as yearly growth (CAGR), so the yearly formula is the right one to use for them. Compare frequencies with the compound interest calculator.
Lump sum formula in Excel or Google Sheets
=100000*(1+12%)^10returns 310585.=FV(12%,10,0,-100000)gives the same answer using the built-in function.- For monthly compounding:
=FV(12%/12,10*12,0,-100000).
Reversing the formula
How much to invest today for a target: P = FV ÷ (1 + r)t. To have 1 crore in 15 years at 12%, you need to invest about 18,26,963 today.
What return did I earn (CAGR): r = (FV ÷ P)1/t − 1. If 1 lakh became 3 lakh in 10 years, the yearly return was about 11.6%.
How long to double: the rule of 72 says divide 72 by the return. At 12% that is about 6 years (the exact figure is 6.1 years).
Lump sum vs SIP: same money, different results
Suppose you have 12 lakh to invest over 10 years at 12%:
- Invested all at once as a lump sum, it grows to about 37,27,018.
- Invested as 10,000 a month through a SIP, it grows to about 23,23,391.
The lump sum wins on paper because all the money works for the full 10 years. In real markets, a SIP spreads your entry over time, which reduces the risk of investing everything just before a fall. If you already have the money, a lump sum usually earns more; if you invest from monthly income, a SIP is the natural choice.
Remember inflation
Future values are in future money. At 6% inflation, a 12% return is about 5.7% in real terms. Use the inflation calculator to see what your future amount is worth in today's prices.
Calculators used in this guide
Lump sum investment formula – FAQs
What is the lump sum investment formula?
FV = P × (1 + r)^t, where P is the amount invested, r is the yearly return as a decimal and t is the number of years.
How do I calculate lump sum returns in Excel?
Use =P*(1+r)^t, for example =100000*(1+12%)^10, or the built-in =FV(12%,10,0,-100000). Both return about 3,10,585.
How much will 1 lakh become in 10 years at 12%?
About 3,10,585 with yearly compounding.
Is lump sum better than SIP?
With the same total amount and return, a lump sum usually grows more because all the money is invested for longer. A SIP reduces the risk of bad timing and suits monthly income.
Further reading: Compound interest (Wikipedia) · Compound Interest Calculator (Investor.gov, U.S. SEC)