Goal SIP Calculator

What is a goal SIP?

A goal SIP works backwards from a number you actually care about — a home down payment, a child’s college fund, a Rs 1 crore retirement corpus — and tells you the monthly SIP you must invest to get there. An ordinary SIP calculator asks “if I invest X, what will I have?” This tool flips the question: “I need Y by a certain date, so what should X be?” That makes it the natural starting point for any real financial goal.

The calculator also accounts for money you have already saved. If you have a lumpsum sitting in a fund or bank today, it keeps growing on its own, so it shrinks the monthly SIP you still need to add.

How the goal SIP is calculated

Two things happen. First, any existing savings grow as a lumpsum to the goal date. Second, whatever gap remains is filled by a monthly SIP, using the standard start-of-month (annuity-due) future-value formula:

Lumpsum FV = C × (1 + i)^n

SIP = (Target − Lumpsum FV) ÷ ( ((1 + i)^n − 1) ÷ i × (1 + i) )

• C — current savings invested today
• i — monthly return = annual return ÷ 12 ÷ 100; n — months = years × 12

Both legs use the same monthly compounding, so your existing savings and your new SIP grow on identical assumptions.

How tenure changes the required SIP

Time is the single biggest lever. The longer you give a goal, the smaller each monthly cheque, because compounding does more of the work. Here is the monthly SIP needed to build Rs 1 crore at 12%, by how many years you allow:

Stretching the same Rs 1 crore goal from 5 years to 25 years cuts the monthly outlay from over Rs 1.2 lakh to about Rs 5,300 — and you contribute far less in total because the market fills the rest. This is why starting early matters more than investing large amounts.

Monthly SIP needed for other goal amounts

Rs 1 crore is the goal people name most often, but it is rarely the right one. The grid below gives the monthly SIP required for a range of targets at an assumed 12% return, with no existing savings. Find your target down the left and your timeline across the top.

The grid is exactly linear in the target, which is worth knowing because it makes the arithmetic easy to do in your head: doubling the goal doubles the monthly SIP, and halving it halves the SIP. What is not linear is time — Rs 1 crore in 25 years costs Rs 5,270 a month, while the same crore in 10 years costs Rs 43,041, eight times as much for two and a half times less waiting.

So to make Rs 1 crore in 10 years you need about Rs 43,041 a month, and to make Rs 1 crore in 15 years about Rs 19,819 a month, both at 12%. If either number is out of reach, the fix is usually more time rather than a higher assumed return — see the next section for why chasing the return assumption is the more dangerous of the two levers.

Why your return assumption matters

The expected return is an assumption, not a promise, and small changes move the required SIP a lot. The table below shows the monthly amount needed for Rs 1 crore in 15 years at different return rates:

Assuming 14% instead of 8% almost halves the SIP you think you need — but if markets under-deliver, you fall short of the goal. For planning, use a realistic 10–12% for diversified equity funds, review progress every year, and treat a lower assumption as a built-in safety margin. You can sanity-check any fund’s actual delivered return with the CAGR calculator.

Using an existing lumpsum

Money you have already saved does part of the job for you. Suppose you want Rs 1 crore in 15 years at 12%: with nothing saved you need Rs 19,819 a month, but with Rs 5 lakh already invested the required SIP drops to about Rs 13,877, because that Rs 5 lakh grows to roughly Rs 30 lakh on its own. If your lumpsum is large enough to reach the target by itself, the required SIP falls to zero — for example Rs 20 lakh invested today at 12% already crosses Rs 1 crore in 15 years. To model a pure one-time investment, use the lumpsum calculator.

The step-up SIP alternative

A fixed monthly SIP can feel heavy at the start, especially for a big goal on a short runway. A step-up SIP lets you begin with a smaller amount and raise it by a set percentage — often 10% — every year as your income grows. Because the larger contributions arrive in later years and still compound, you can reach the same target starting lower than a flat SIP requires. If the goal SIP here looks steep today, a step-up plan that tracks your salary hikes is usually the more realistic path to the same corpus.

Don’t forget inflation

A goal set in today’s rupees will cost more by the time you get there. Rs 1 crore in 15 years buys far less than Rs 1 crore today — at 6% inflation it is worth roughly Rs 42 lakh in current terms. Before locking a target, inflate it to its future value with the inflation calculator so your goal reflects what you will actually need, not what the number looks like now.

How to use this calculator

1. Enter your target amount — the corpus you want, ideally inflation-adjusted to the goal date.
2. Set the time to goal in years and a realistic expected return.
3. Add any current savings already earmarked for this goal.
4. Read off the monthly SIP required, plus how much you invest versus how much the market contributes.

Revisit the plan once a year: as your corpus grows and your income rises, you can step up the SIP or shorten the timeline. Once the goal is met, plan steady withdrawals from it using the SWP calculator.