Formula
FV = P × [((1 + i)ⁿ − 1) ÷ i] × (1 + i)i = annual rate ÷ 12 ÷ 100; n = number of months
- P — monthly amount
- Step-up: P rises by the chosen percent every 12 months
- Investing at the end of each month omits the final × (1 + i)
Each month's amount earns monthly growth for as long as it stays invested.
Worked example
5,000 a month, 12%, 10 years
- Monthly investment
- 5,000
- Expected return per year
- 12 %
- Investment period (years)
- 10 years
- Investments happen
- At the start of each month (usual SIP formula)
- Currency symbol
- ₹ Rupee (INR)
Estimated maturity value
₹11,61,695.38
Total invested: ₹6,00,000.00
Estimated returns: ₹5,61,695.38
Value as a multiple of the amount invested: 1.936
How it works
5,000 a month for 10 years at an assumed 12% a year puts in 6,00,000 and projects to about 11,61,695 — roughly 5,61,695 of growth — if each instalment is invested at the start of the month. Starting a year earlier or increasing the amount by 10% each year changes the result far more than small changes in the return you assume.
Real returns vary year to year and are never guaranteed; fund costs, exit loads and taxes are not deducted. Treat the figure as a planning illustration. For one-off investments use the Compound Interest Calculator; for fixed products see FD Calculator and RD Calculator; to turn a past result into a yearly rate use CAGR Calculator.
Assumptions and limits
- Constant return every month; no fees, tax or missed instalments.
- Maximum 50 years.