SIP formula
Each instalment is invested at the start of the month and compounds monthly:
P is the monthly SIP, r is the monthly return (yearly % ÷ 12 ÷ 100) and n is the number of months. With a step-up, the calculator raises P every 12 months and adds up each month's growth.
Why starting early matters
At 12%, ₹5,000 a month for 30 years becomes about ₹1.76 crore, but for 20 years only about ₹50 lakh. The extra 10 years add ₹6 lakh of investment but more than ₹1.2 crore of value. That is compounding.
Picking a realistic return
- Large-cap equity funds: often assumed at 10% to 12% over long periods.
- Hybrid funds: around 8% to 10%.
- Debt funds: around 6% to 7.5%.
Use a conservative number for planning. For guaranteed, tax-free growth compare with the PPF calculator or a bank FD calculator.