SIP Calculator
Estimate SIP future value, invested amount, and potential gains.
Written by Anil Gautam · Updated
How does the SIP calculator work out the future value?
Each instalment is treated as invested at the start of the month and grown at one-twelfth of the annual return you enter. The formula is P × ((1 + i)^n - 1) ÷ i × (1 + i), where P is the monthly amount, i is the annual rate divided by 12 and n is the number of months. With the starting values, ₹10,000 a month for 10 years at 12%, i is 1% and n is 120. You invest ₹12,00,000, the projected value is ₹23,23,391 and the estimated gain is ₹11,23,391.
The last (1 + i) term reflects the start-of-month timing. If each instalment went in at the end of the month, the same inputs would give about ₹23,00,387.
Should you enter a fund's CAGR as the expected return?
Dividing 12% by 12 and compounding monthly works out to 12.68% a year. Fund returns over periods longer than a year are normally quoted as an annualised figure compounded once a year, so typing one straight in slightly overstates the result. To model 12% a year compounded annually, enter 11.39 instead: the same ₹10,000 a month for 10 years then grows to ₹22,40,816, which is ₹82,575 less.
Doubling the period does more than doubling either of the other inputs. Stretching it to 20 years at 12% doubles the money invested to ₹24,00,000, but the projected value rises to ₹99,91,479, more than four times the 10-year figure. Halving the instalment to ₹5,000 over 10 years halves every result, so the future value becomes ₹11,61,695.
What does the SIP estimate leave out?
The monthly amount stays fixed for the whole period, with no yearly step-up, and the return is identical every month. Real fund returns vary from year to year, and the order of good and bad years changes the final value even when the average return is the same. Taxes and exit loads are not deducted, and inflation is not removed: at 6% a year, ₹23,23,391 in ten years buys roughly what ₹12.97 lakh buys today. With a 0% return the future value equals the amount invested, and the estimated gain is ₹0.
A bank recurring deposit at a fixed rate is better handled by the RD Calculator, which uses quarterly compounding. For a one-time investment, use the Compound Interest Calculator, and the FIRE Retirement Calculator shows how a monthly investment builds toward a retirement target once inflation is included. Results are rounded to whole rupees and calculated in your browser.