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MoneyAugust 16, 2026 · 6 min read

SIP calculator: how much to invest monthly to reach your goal

The number that matters is not the return, it's the monthly amount. Here's how SIP compounding actually works, what it takes to reach ₹1 crore, and how to check your own plan in seconds.

The question is the monthly amount, not the return

Most SIP planning starts with "what return can I get?" It is the wrong first question. Returns are not something you control. The monthly amount is — and it is the only lever that guarantees progress.

A SIP works on the future value of an annuity: every month you add money, the whole pot compounds, and the number that comes out the other end depends far more on how long you stay in than on a percent or two of return.

What a ₹5,000 monthly SIP actually grows to

The numbers do the convincing. At a 12% annual return, compounded monthly:

  • 10 years — about ₹11.6 lakh
  • 20 years — about ₹50 lakh
  • 25 years — about ₹95 lakh

Notice what happened between 10 and 25 years. The invested amount only grew from ₹6 lakh to ₹15 lakh, but the corpus grew from ₹11.6 lakh to ₹95 lakh. The last years do almost all the work because compounding accelerates. That is why starting early beats investing more, every single time.

How much to invest for ₹1 crore

To reach roughly ₹1 crore at 12% a year:

  • Over 25 years — about ₹5,300 a month
  • Over 20 years — about ₹10,000 a month
  • Over 15 years — about ₹20,500 a month

The pattern is brutal and freeing at once: every year you delay, the monthly amount needed climbs steeply. Starting at 25 instead of 30 nearly halves what you need to invest.

These are estimates, not promises. Returns vary, and 12% is a middle assumption — equity funds in India have historically returned roughly 10–14% over long periods. Try all three numbers and plan for the range, not the point.

Run your own numbers

Instead of relying on round numbers, run the SIP calculator with your actual monthly amount and horizon. It uses the standard annuity formula with monthly compounding, and shows you the invested amount and the gains separately, so you can see exactly how much of your corpus is your own money and how much is growth.

The mirror question: can you afford the loan instead?

There is a useful symmetry here. The same monthly discipline that builds a corpus through a SIP can also be the monthly payment that buys a house — and the math works the same way, just in reverse. If you are choosing between investing and borrowing, the loan EMI calculator tells you what a given monthly payment buys you as a loan, while the SIP calculator tells you what it builds as an investment.

The rule that actually matters

Do not chase the return. Pick a sensible middle estimate, fix a monthly amount you can sustain for decades, and start now. The SIP calculator takes ten seconds and gives you the number that should drive your budget — the monthly amount, not the headline return.