How it works
This is the inverse of a SIP calculator. Instead of asking what ₹10,000 a month becomes, it asks what monthly amount produces ₹15 lakh by a given date — which is the question people actually start with when planning a car, a wedding, a house deposit or a course.
Two refinements change the answer materially. First, the goal inflates: education costs have historically risen faster than general inflation, cars roughly in line with it. Second, money you have already set aside keeps compounding, so it reduces the monthly requirement by more than its face value.
Monthly = (Future target − Current savings x (1+i)^n) x i ÷ (((1+i)^n − 1) x (1+i))
- i is the monthly return: (1 + annual rate)^(1/12) − 1, so twelve months compound back to exactly the rate you entered
- n is the number of months to the goal
- Future target is today’s cost grown by the inflation rate you set
- Contributions are assumed at the start of each month, the standard SIP convention
- Price the goal in today’s rupeesWhat would it cost if you bought it this month? The calculator handles the inflating.
- Set an honest deadlineThe horizon matters more than the return. Doubling the time roughly halves the monthly amount.
- Match the return to the horizonUnder three years, use debt funds or FDs at 6–7%. Five years or more allows equity exposure at 10–12%.
- Subtract what you already haveExisting earmarked savings compound alongside your contributions and cut the monthly figure noticeably.
- Automate on salary dayA standing instruction dated for the day after your salary credit is what turns the number into a result.
A worked example
Karthik wants a car that costs ₹15,00,000 today. At 6% inflation it will cost about ₹18,94,000 in four years. He has ₹1,00,000 set aside and expects roughly 10% on a balanced fund.
His existing ₹1,00,000 grows to about ₹1,49,000 over the period, so he needs the remaining ₹17,45,000 from contributions — around ₹29,500 a month. If he can wait six years instead, the monthly figure drops to roughly ₹19,800, because a longer runway lets compounding do more of the work.
Common mistakes
- Using today’s price as the target for a goal five or more years away
- Putting a two-year goal into equity, where a bad year forces you to postpone or accept less
- Ignoring money already earmarked, which overstates the monthly requirement
- Setting the deadline by wishful thinking rather than by what the monthly figure allows
- Funding the goal from whatever is left at month-end instead of a standing instruction
Where to park money by goal horizon
| Time to goal | Suitable instruments | Realistic return |
|---|---|---|
| Under 1 year | Savings account, liquid fund | 4–6% |
| 1–3 years | Short-duration debt fund, FD, RD | 6–7.5% |
| 3–5 years | Hybrid or balanced advantage fund | 8–10% |
| 5–10 years | Diversified equity funds via SIP | 10–12% |
| Over 10 years | Equity-heavy portfolio, index funds, NPS | 11–13% |
Frequently asked questions
It depends on the amount, the deadline and the return you can realistically earn. Enter all three above and the calculator gives the exact figure, including the effect of inflation on the target and growth on what you have already saved.
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How BudgetAnalyzer helps
Knowing the monthly figure is the easy half; the hard half is finding it in your budget. BudgetAnalyzer suggests realistic category targets from your own last three to six months of spending, so you can see exactly which categories have room before you commit to a standing instruction.