What a retirement corpus actually has to be

"A crore should do it" is the most common retirement plan in India and one of the least likely to work. The reason is not pessimism about returns. It is that the number has to be built from the spending it must fund, in the money of the year it will be spent, and almost nobody does that second part.

Here is the calculation, with every assumption named.

Step one: what the lifestyle will cost

Assumption: your household spends ₹60,000 a month today, and inflation averages 6% over the next 25 years.

Monthly spending today	₹60,000
The same lifestyle in 25 years	₹2,57,512 a month

Not a worse lifestyle or a better one. The same one, costing four times as much, because that is what 6% compounding for twenty-five years does to a price.

This is the step people skip. Planning for ₹60,000 a month in 2051 is planning to live on roughly a quarter of what you live on now.

Step two: the corpus that funds it

Assumption: you draw 4% of the corpus in the first year and adjust it for inflation thereafter — a widely used rule of thumb, derived from historical market data in another country, and not a guarantee anywhere.

₹2,57,512 a month is ₹30,90,147 a year. At a 4% withdrawal rate:

Corpus required	₹7,72,53,673

About ₹7.73 crore. Against which "a crore should do it" is not a conservative plan; it is roughly an eighth of one.

Step three: what it takes to get there

Assumption: you invest monthly for the full 25 years and earn a steady annual return.

Assumed return	Monthly investment needed	Total you contribute
10%	₹57,743	₹1,73,22,871
12%	₹40,710	₹1,22,13,150

Two points fall out of that table.

Returns do the heavy lifting. At 12% you contribute ₹1.22 crore and end with ₹7.73 crore. Roughly 84% of the final corpus is growth, not contribution. That is the entire argument for starting early — compounding needs time more than it needs money.

Two percentage points cost ₹17,033 a month. The gap between a 10% and a 12% assumption is not academic; it is a different monthly commitment entirely. Which is why planning on the optimistic number and hoping is the common failure mode.

Where this calculation is weakest

Being honest about the limits:

The withdrawal rate is a rule of thumb, not a law. It came from historical analysis of a different market over a different period. Indian inflation, Indian market behaviour and your own retirement length may not oblige.

Nobody earns a steady 12%. Returns arrive unevenly, and the order matters — a severe fall in the first years of retirement, while the corpus is largest and you are drawing from it, does far more damage than the same fall later. This is called sequence risk and a single average return hides it completely.

Spending is not flat in retirement. It often falls in the early years as travel reduces and rises later as healthcare grows. Medical inflation in India has generally run ahead of general inflation, which argues for treating health cover as a separate line rather than assuming the corpus absorbs it.

You may not have 25 years. If you are 15 years out, the same corpus needs a much larger monthly figure, and the honest options are to save more, work longer or plan to spend less. There is no fourth option that arithmetic permits.

What to do with the number

Not panic. Use it as a direction rather than a verdict. What matters most is that the figure is built from your spending and your horizon, not borrowed from a headline, and that you revisit it as both change.

Then check the sensitivity. Run the calculation at 10% and at 12%, and at 6% inflation and at 7%. The spread between those runs is the real answer — a range you are working within, rather than a single number that implies a precision nobody has.

Build your own on the SIP calculator for the monthly figure and the NPS calculator if a chunk of your retirement sits there, and read the inflation guide for why the first step above is the one that decides everything after it.