How SIP returns are calculated
Each instalment is invested at the start of the month and grows at the assumed return, compounded monthly. For a SIP that stays the same every month, that gives a standard formula.
Value = P × [(1 + i)n − 1] ÷ i × (1 + i)
P is the monthly SIP, i is the monthly rate (annual return ÷ 12 ÷ 100) and n is the number of months.
For ₹10,000 a month at 12% for 15 years, i is 0.01 and n is 180. You invest ₹18 lakh, and the formula gives about ₹50.46 lakh.
Why a step-up makes such a difference
With a step-up, your SIP rises every year, so later instalments are larger and each one still has years left to grow. In the example, raising ₹10,000 by 10% a year means you invest ₹38.13 lakh in total, and the estimated value grows to ₹86.84 lakh, about ₹36.38 lakh more than keeping the SIP flat.
Working backwards works too: to aim for ₹1 crore in 15 years at 12% with a 10% yearly step-up, you would start at about ₹11,600 a month. Choose "I have a target" above to try your own goal.
Today's money
Prices rise over time, so a large number in 15 years buys less than it would today. At 6% inflation, ₹86.84 lakh in 15 years is worth about ₹36.23 lakh in today's money. Planning in today's money keeps goals realistic.
Questions people ask
Is the final amount guaranteed?
No. Mutual fund returns go up and down with the market, and the return you enter is an assumption. Try a few different rates to see a range of outcomes.
What return should I assume?
It depends on the kind of fund and how long you invest. Many people check a cautious, a middle and an optimistic rate rather than relying on one number. Past returns do not guarantee future ones.
Do I have to increase my SIP by the same percentage every year?
No. A fixed yearly step-up is a simple way to plan. In practice you can raise, pause or lower your SIP whenever you like.
Are my numbers saved anywhere?
No. Everything is calculated in your browser. A share link carries the numbers in the link itself, not on our servers.
Method and sources
Instalments at the start of each month, assumed annual return compounded monthly at rate ÷ 12, step-up applied every 12 months. Today's value divides the final amount by (1 + inflation) for each year. These are illustrations based on an assumed return, not a forecast or a recommendation of any fund. How we calculate.
Last reviewed 22 Oct 2026 by the WealthFeedz team.