Updated 30 September 2026
What a lumpsum investment is
A lumpsum is money you invest in one go and then leave alone: a bonus, a matured fixed deposit, the proceeds of a sale. Unlike a SIP, all of it starts working on day one. That's its big advantage, and also its risk, because the whole amount goes in at one price.
This calculator shows what that money could grow to at a steady yearly return, or works backwards from a target to tell you how much to invest today. It assumes the same return every year. Real investments don't behave like that, so use the result to plan, not to predict.
How to use it
- Choose What it grows to, or Amount for a goal to work backwards from a target.
- Enter the amount (or target), the yearly return you expect and the number of years.
- Open Inflation to change the rate used for the value in today's money. It's 6% by default.
- Tap or hover over a year in the chart to see its numbers, or open the year-by-year table.
The lumpsum formula
Value = P × (1 + r)^t
P is the amount you invest, r the yearly return and t the number of years. ₹1,00,000 at 12% a year for 10 years becomes 1,00,000 × 1.12^10 = ₹3,10,585, a little over three times the money.
The growth isn't spread evenly. In the first year the investment earns ₹12,000. In the tenth year it earns ₹33,277, nearly three times as much, on the same original amount. Each year's return is earned on everything before it, which is why the bars in the chart get taller faster as time goes on.
What ₹1 lakh grows to
| Time | At 6% | At 8% | At 10% | At 12% | At 15% |
|---|---|---|---|---|---|
| 5 years | ₹1.34 lakh | ₹1.47 lakh | ₹1.61 lakh | ₹1.76 lakh | ₹2.01 lakh |
| 10 years | ₹1.79 lakh | ₹2.16 lakh | ₹2.59 lakh | ₹3.11 lakh | ₹4.05 lakh |
| 15 years | ₹2.4 lakh | ₹3.17 lakh | ₹4.18 lakh | ₹5.47 lakh | ₹8.14 lakh |
| 20 years | ₹3.21 lakh | ₹4.66 lakh | ₹6.73 lakh | ₹9.65 lakh | ₹16.37 lakh |
| 25 years | ₹4.29 lakh | ₹6.85 lakh | ₹10.83 lakh | ₹17 lakh | ₹32.92 lakh |
| 30 years | ₹5.74 lakh | ₹10.06 lakh | ₹17.45 lakh | ₹29.96 lakh | ₹66.21 lakh |
For another amount, scale the figures: ₹5 lakh is five times the table, ₹50,000 is half.
The Rule of 72
A quick way to see how long money takes to double: divide 72 by the yearly return. At 12% that's 72 ÷ 12 = 6 years. The calculator shows the exact figure too. The rule is close for normal returns and gets less accurate at very high or very low ones.
| Return a year | Rule of 72 | Exact |
|---|---|---|
| 6% | 12.0 years | 11.9 years |
| 8% | 9.0 years | 9.0 years |
| 10% | 7.2 years | 7.3 years |
| 12% | 6.0 years | 6.1 years |
| 15% | 4.8 years | 5.0 years |
It works the other way as well. If you want to double your money in 8 years, you need about 72 ÷ 8 = 9% a year.
Working backwards from a goal
Switch to Amount for a goal and the calculator divides your target by the growth factor:
Invest today = Target ÷ (1 + r)^t
| Time | At 8% | At 10% | At 12% |
|---|---|---|---|
| 5 years | ₹6,80,584 | ₹6,20,922 | ₹5,67,427 |
| 10 years | ₹4,63,194 | ₹3,85,544 | ₹3,21,974 |
| 15 years | ₹3,15,242 | ₹2,39,393 | ₹1,82,697 |
| 20 years | ₹2,14,549 | ₹1,48,644 | ₹1,03,667 |
At 12%, reaching ₹10 lakh takes ₹3,21,974 invested today with 10 years to go, but only ₹1,03,667 with 20 years. Starting earlier sharply cuts the amount you need. The result board also shows the monthly SIP that would reach the same target, if you don't have the lumpsum.
Lumpsum or SIP?
Compare ₹1,20,000 invested once with ₹1,000 a month for 10 years, the same total, both at 12% a year:
- Lumpsum: ₹3,72,702
- SIP: ₹2,24,036
With a steady return, the lumpsum wins easily, because every rupee is invested for the full 10 years. The SIP's later installments barely have time to grow. The calculator shows this comparison under every lumpsum result.
Markets aren't steady, though. The Nifty 50 lost about half its value in 2008, and someone who invested a lumpsum at the January 2008 high waited years just to get back to even. A SIP spreads the buying over many prices, so a bad entry point matters less. So the trade-off is: a lumpsum gives more growth if returns are steady, a SIP gives a smoother ride.
A middle path many investors use is a systematic transfer plan (STP). The lumpsum goes into a liquid or debt fund, and a fixed amount moves into an equity fund of the same fund house at regular intervals, such as every week or month. Your money is invested from day one, but it enters equity gradually instead of at one day's price. Each transfer counts as a redemption from the first fund, so it can be taxed. To plan a monthly amount, use the SIP calculator.
Don't forget inflation
₹3,10,585 in 10 years is not the same as ₹3,10,585 today. At 6% inflation it buys about what ₹1,73,429 buys now. The investment still grew in real terms, but by far less than the headline number suggests. India's official inflation target is 4%, with a band of 2% to 6%; the calculator uses 6% by default to stay on the cautious side.
Tax on lumpsum returns
The result is before tax. A lumpsum has a single purchase date, which keeps tax simple. For equity mutual funds in FY 2026-27, gains on units held more than 12 months are long-term and taxed at 12.5% above ₹1.25 lakh a year (one limit across all your listed shares and equity funds); units sold within 12 months are taxed at 20%. Gains in debt funds bought from 1 April 2023 are taxed at your slab rate. Surcharge and cess apply on top, and budgets can change these rules.
Common lumpsum mistakes
- Waiting for the perfect entry. Money sitting in a savings account while you wait for a dip can miss more growth than a bad entry would have cost.
- Putting money you'll need soon into equity. If you need it within a few years, a crash can force you to sell at a loss.
- Planning with a best-case return. Check the result at a lower return too; the note under every result shows 2% lower and 2% higher.
- Selling in the first year. Many equity funds charge an exit load, often 1%, on units redeemed within a year, and short-term gains are taxed at the higher rate.
To see how compounding frequency and regular additions change the picture, try the compounding calculator.