Investment maths — assumptions are yours

Goal planner

Enter a goal in today's rupees — education, a house, retirement — and see the monthly SIP or one-time lumpsum it needs, after accounting for inflation until the goal date.

Goal amount (in today's rupees)

Years to the goal

Expected return (% p.a.)

Adjust the goal for inflation

Inflation (% p.a.)

What costs ₹1 today will cost more at the goal date; the target is inflated accordingly.

Monthly SIP needed

—

Goal in today's rupees	—
Target at the goal date	—
Total SIP outgo	—
Or a one-time lumpsum today	—

Show the math

Required SIP inverts the SIP formula: P = target ÷ [((1+i)ⁿ − 1)/i × (1+i)], i = return ÷ 12.
Lumpsum alternative discounts the target: P = target ÷ (1+r)ᵗ.

Why inflate the goal

A goal that costs ₹1 crore today will not cost ₹1 crore in 15 years. At 6% inflation it roughly doubles every 12 years — so planning against today's price systematically undershoots. This planner first inflates today's cost to the goal date, then computes the SIP (instalment at the start of each month, compounding monthly) or the single upfront amount that reaches that inflated target at your expected return.

Related: SIP vs lumpsum · step-up SIP.

For information only — not investment advice. Returns and inflation are your assumptions; real outcomes will differ. This page computes the arithmetic of a goal; it does not recommend products or asset allocations.