Suppose you invest a one-time lump sum of Rs 5,00,000 in an equity mutual fund and leave it for 15 years, expecting a 12 percent annual return. The future value is the investment compounded yearly, so Rs 5,00,000 multiplied by 1.12 raised to the power 15. That works out to about Rs 27,36,783. The wealth gained is roughly Rs 22,36,783, which means the money grows to about 5.47 times what you put in over 15 years. This is the power of compounding over a long horizon: the same 12 percent return on a much shorter horizon produces far less, because most of the growth in a lump sum comes in the final years when the base has already multiplied. The figures here are pre-tax and assume a steady return, whereas real equity returns vary year to year.
How it is calculated
The tool uses the compound growth formula for a single sum: future value equals the amount invested multiplied by 1 plus the annual return, raised to the number of years. There are no further contributions, since a lump sum is invested once and left to grow. The wealth gained is the future value minus the amount invested, and the multiple is the future value divided by the investment. The result is pre-tax and assumes a constant annual return, which smooths out the ups and downs of real markets. Equity gains held over a year are taxed as long-term capital gains at 12.5 percent above the Rs 1.25 lakh annual exemption, so the actual money in hand at redemption is a little below the maturity shown. For a windfall, many investors split the amount and deploy part as a lump sum and the rest gradually through an STP to reduce timing risk.
Frequently asked questions
Lumpsum vs SIP?
Lumpsum wins when markets are low or trending up. SIP reduces timing risk via rupee-cost averaging. For a large windfall, many split: part lumpsum, rest as STP over 6-12 months.
How is lumpsum mutual fund gain taxed in India?
Equity fund gains held over 12 months are long-term capital gains (LTCG). The first Rs 1.25 lakh of LTCG in a financial year is exempt; gains above that are taxed at 12.5 percent without indexation as per the Finance Act 2024. Gains on units held 12 months or less are short-term capital gains taxed at 20 percent.
What CAGR should I use for equity mutual funds?
Indian large-cap equity funds have historically delivered 10 to 13 percent CAGR over rolling 10-year periods, while mid and small-cap funds have ranged from 12 to 16 percent with higher volatility. Financial planners commonly use 10 to 12 percent as a conservative planning assumption. Past performance does not guarantee future returns.
Does this calculator account for inflation?
No, the maturity value shown is nominal, meaning it is not adjusted for inflation. To find the real (inflation-adjusted) value, divide the maturity amount by (1 plus the assumed inflation rate) raised to the number of years. India long-run CPI inflation has averaged around 5 to 6 percent, so a 12 percent nominal return translates to roughly 6 to 7 percent real return.