What is a goal-based SIP calculator?

It works the SIP calculation backwards. Instead of asking what a contribution will grow into, it asks what contribution is needed to reach a stated amount within a stated period, taking account of what you have already saved.

How is the required SIP amount calculated?

Existing savings are compounded forward to the end of the period and subtracted from the target. The remaining gap is divided by the future value of a ₹1 monthly SIP over the same period, which gives the monthly amount needed.

Should I enter my target in today's money or future money?

Future money. If you enter today's cost, inflation will leave the plan short. Use the inflation calculator to convert your goal into the amount it is likely to cost in the year you need it, then enter that.

What return should I assume for a goal?

That depends on what you will invest in and how long you have, and no calculator can decide it for you. What this one can show is the cost of being wrong — the rate scenario reports the required contribution at 8%, 10% and 12% so you can see how much the answer moves.

What if the required SIP is more than I can afford?

The three scenario tables show the three levers directly: extend the horizon, reduce the target, or accept that a lower contribution reaches a smaller number. A step-up SIP is a fourth option if your income is likely to rise.

Is reaching the goal guaranteed if I invest this amount?

No. The figure is what the assumed rate implies, and market-linked returns vary. Treat it as a plan to review rather than a commitment that guarantees the outcome.

Investment · FINANCIAL TOOLS

Goal-Based SIP Calculator

Start from the amount you need and work backwards to the monthly investment it requires.

Understand the calculation

Calculation logic, formula, example and guardrails behind the estimate.

How it works

The calculator first projects what you already have. Existing savings are compounded forward at the same assumed rate over the same period, which usually covers a meaningful share of the target on its own.

Whatever the target exceeds that by is the gap the new contributions have to fund. If existing savings alone are projected to clear the target, the required contribution is zero and the calculator says so rather than returning a negative number.

More detail

The required monthly amount is then the gap divided by the future value of a ₹1 monthly SIP over the same period. That divisor comes from the same function the forward SIP calculator uses, so the two are exact inverses — feed the required contribution back into the SIP calculator and you land on the gap.

Because the answer scales linearly with the gap, doubling the target roughly doubles the contribution, but halving the time far more than doubles it. The duration scenario below makes that asymmetry visible.

Before setting a target, work out what it will actually cost by then — the inflation calculator converts today's price into future rupees.

If your contribution can rise each year, the starting amount needed is lower — model it with the step-up SIP calculator.

Formula

P = ( Target − Savings × (1 + i)ⁿ ) ÷ ( ((1 + i)ⁿ − 1) ÷ i × (1 + i) )

The numerator is the shortfall after existing savings have grown; the denominator is the future value of a ₹1 monthly SIP. When savings alone reach the target the numerator goes negative and the required contribution is reported as zero.

P: Required monthly investment
Target: The amount you want at the end
Savings: What you have already set aside for this goal
i: Monthly rate — the assumed annual return divided by 12, as a decimal
n: Number of monthly instalments (years × 12)

Worked example

A ₹50,00,000 target in 10 years, with ₹5,00,000 already saved, at an assumed 12% return.

01Monthly rate (i)12% ÷ 12 = 1% = 0.01
02Instalments (n)10 × 12 = 120
03Existing savings grow to₹5,00,000 × 1.01¹²⁰ ≈ ₹16,50,193
04Gap to fund₹50,00,000 − ₹16,50,193 ≈ ₹33,49,807
05Future value of a ₹1 SIP((1.01¹²⁰ − 1) ÷ 0.01) × 1.01 ≈ 232.34
06Required monthly SIP₹33,49,807 ÷ 232.34 ≈ ₹14,418
07Total contributed₹14,418 × 120 ≈ ₹17,30,160

The ₹5 lakh already saved does roughly a third of the work by itself, because it has the full ten years to compound. Starting a goal with something already set aside is worth considerably more than the amount suggests.

Important considerations

01
Set the target in future rupees
A goal costing ₹50 lakh today will cost considerably more in ten years. Run the amount through the inflation calculator and use the inflated figure here, or the plan is aiming at the wrong number.
02
Assume conservatively, then check
The rate scenario shows what happens at 8%, 10% and 12%. If the plan only works at the highest assumption, it is worth either extending the horizon or lowering the target while there is still time to adjust.
03
Time is the most powerful input
Halving the horizon roughly triples the required contribution at typical rates, because contributions made late have almost no time to compound. Starting earlier is worth more than finding a better rate.
04
Match the assumed return to the horizon
A high equity assumption over a three-year goal carries real risk of falling short, since short periods offer no time to recover from a bad one. Shorter goals usually justify more conservative assumptions.
05
Revisit the plan periodically
Returns will not arrive as assumed. Re-running this calculation once a year with your actual balance as the current savings figure keeps the required contribution honest.

Limitations

The target is treated as a nominal future amount. If you set it in today's prices, the plan will fall short in real terms — convert it with the inflation calculator first.
It assumes a constant return. A run of poor years near the end of the period can leave the goal short even if the average was met.
It assumes a level contribution. If yours will rise with income, the step-up SIP calculator will show a lower starting figure for the same target.
Reaching a goal exactly is not something a projection can promise; treat the required contribution as a planning floor rather than a precise prescription.

Frequently asked questions

Common questions about the goal-based sip calculator and the assumptions behind it.

Next useful checks

Move from this result to the next decision without hunting through the full calculator list.

SIP vs Lumpsum CalculatorCompare investing all at once against monthly investing.CAGR CalculatorConvert start and end values into an annual return.

Related calculators

Other tools that answer questions close to this one.

All investment calculators

Investments

SIP Calculator

Project what a fixed monthly mutual fund SIP could grow to at an assumed rate of return.

Open calculator

Investments

Step-up SIP Calculator

Model a SIP that increases by a fixed percentage every year and compare it with a level SIP.

Open calculator

Investments

Inflation Calculator

See what today's money would cost in future, and what it would still buy if left uninvested.

Open calculator

Investments

Lumpsum Calculator

See how a single one-time investment could compound over a chosen number of years.

Open calculator

Investments

Compound Interest Calculator

Combine a starting amount with regular contributions to see how compounding builds on both.

Open calculator

Loans & Credit

Education Loan Calculator

Work out an education loan instalment with the moratorium modelled — including what capitalised interest adds to the debt.

Open calculator

Browse all calculators

Disclaimer

This calculator is provided for general information and planning only. It is not investment, tax or legal advice, and it does not take your personal circumstances into account. Outputs are estimates based on the assumptions stated on this page, exclude taxes and charges unless said otherwise, and market-linked returns are not guaranteed — the value of investments can fall as well as rise. Lending terms, rates and eligibility are decided by the lender. For advice on your own situation, speak to a qualified professional, several of whom you can consult on Finvestalk.