Lumpsum Calculator
See what a one-time mutual fund investment could grow to, with a year-by-year table and an inflation-adjusted value.
Was this tool helpful?
Thanks for the feedback!
The lumpsum calculator projects how a single, one-time investment in a mutual fund could grow at a return you choose. It lists the value at the end of every year and converts the final amount into present-day purchasing power using an inflation rate. It is meant for people investing a bonus, a maturing FD or the proceeds of a property sale in one go who want to see a range of possible outcomes before committing.
What the four inputs control
- One-time investment (₹): the amount invested on day one. Enter digits without commas.
- Expected return (% a year): prefilled with 12%. Any rate from −20% to 40% is accepted, so you can also test a losing stretch. Treat it as an assumption to test, not a forecast.
- Investment period (years): whole years from 1 to 50. A value such as 7.5 is rounded to 8.
- Inflation (% a year, optional): prefilled with 6% and limited to 0% to 20%. Clear it or enter 0 and the inflation-adjusted line is dropped from the result.
After Calculate returns, the result shows the estimated value, the amount invested, the estimated gain and a growth multiple to two decimals. When inflation is above zero it adds what the final sum is worth at current prices. A Year, Value and Gain table follows, with one row for every year of the period.
The formula: one payment, compounded once a year
Future value = P × (1 + r)^t Inflation-adjusted value = Future value ÷ (1 + inflation)^t
P is the amount invested, r the yearly return as a decimal and t the number of years. The tool compounds annually and applies the same rate in every year, so the line it draws is smooth even though fund NAVs are not. A fund's NAV is published after its expense ratio is charged, so a return taken from the fund's own NAV history already includes its costs. If you start from an index return instead, subtract the expense ratio before typing the rate.
₹1 lakh at 12% for 10 years, step by step
- Growth factor: 1.12^10 = 3.10585, so ₹1,00,000 becomes ₹3,10,585. The gain is ₹2,10,585 and the growth multiple 3.11×.
- Inflation factor at 6%: 1.06^10 = 1.79085.
- Adjusted value: ₹3,10,585 ÷ 1.79085 = ₹1,73,429.
On paper the money triples, but it buys only about 1.7 times what ₹1 lakh buys now, a real return near 5.7% a year (1.12 ÷ 1.06 − 1). Extend the period to 20 years and the table reads:
| Year | Value | Gain |
|---|---|---|
| Year 1 | ₹1,12,000 | ₹12,000 |
| Year 5 | ₹1,76,234 | ₹76,234 |
| Year 10 | ₹3,10,585 | ₹2,10,585 |
| Year 15 | ₹5,47,357 | ₹4,47,357 |
| Year 20 | ₹9,64,629 | ₹8,64,629 |
The gain added between year 10 and year 20 (₹6,54,044) is more than three times the gain of the first decade. Staying invested longer matters more than adding a point of return for a short period.
How much the return assumption moves the result
| Return | 10 years | 20 years |
|---|---|---|
| 8% | ₹2,15,892 | ₹4,66,096 |
| 10% | ₹2,59,374 | ₹6,72,750 |
| 12% | ₹3,10,585 | ₹9,64,629 |
All three rows start from ₹1 lakh. Over 20 years, assuming 12% instead of 8% more than doubles the end value. Equity fund returns swing sharply from one year to the next, and the steady path shown here is only an average, so run the tool at a cautious rate and an optimistic one and plan around the lower figure. A larger example: ₹5,00,000 at 10% for 15 years gives ₹20,88,624, a multiple of 4.18×, worth ₹8,71,510 at present prices after 6% inflation.
Tax on redemption and other gaps in the estimate
Every figure is before tax. For Tax Year 2026-27 the Income-tax Act, 2025 continues the capital gains rates set in July 2024:
- Equity-oriented funds held longer than 12 months: long-term gains above ₹1.25 lakh in a tax year are taxed at 12.5%.
- Equity-oriented funds sold within 12 months: short-term gains are taxed at 20%.
- Debt funds (more than 65% in debt) bought on or after 1 April 2023: gains are added to your income and taxed at slab rates, however long you hold them.
If the ₹2,10,585 gain from the example were your only equity gain in the year of sale, ₹85,585 would be taxable. 12.5% of that is ₹10,698, and 4% cess brings it to ₹11,126, leaving about ₹2,99,459 at today's rates. A lump sum in an ELSS fund also counts towards the ₹1.5 lakh Section 80C limit (section 123 of the Income-tax Act, 2025), but only in the old regime, and ELSS units are locked in for three years. The tool does not account for exit loads, the order in which good and bad years arrive, or money added later.
Lump sum, SIP or a staggered STP?
With a steady positive return, investing everything on day one always beats spreading the same money out, because every rupee compounds for the full period. Markets do not rise in a straight line, so many investors with a large sum keep it in a liquid fund and shift it into equity through a systematic transfer plan (STP) over several months, which lowers the damage if a fall comes right after they invest. If your money will arrive as monthly savings rather than all at once, the SIP calculator is the better model, and the SWP calculator shows how a corpus could later pay you a monthly income. Treat these numbers as estimates, not investment or tax advice.