🏖️ Retirement Corpus Calculator
Estimate the retirement corpus you'll need and the monthly SIP required to build it.
Frequently Asked Questions
How do I use the Retirement Corpus Calculator?
Enter your Current Age, Retirement Age, Life Expectancy, Current Monthly Expenses, Inflation Rate, Expected Return Before Retirement, Expected Return After Retirement and any Existing Retirement Savings, then click "Calculate" to see your required Retirement Corpus, Monthly Expense at Retirement, Required Monthly SIP, Corpus Shortfall, Balance at Life Expectancy, and years to/in retirement, along with a corpus accumulation and drawdown chart and year-by-year projection table.
How is the retirement corpus calculated?
First, your current monthly expenses are inflated forward to the year you retire, using your inflation rate. Then, the calculator simulates your retirement years month by month: each year you withdraw an inflation-adjusted amount from the corpus, and the remaining balance earns your post-retirement return. The corpus needed is the amount that, when drawn down this way, lasts exactly until your life expectancy with a zero balance.
How is the required monthly SIP calculated?
The calculator works backwards from the corpus target. Assuming a step-up SIP (one that increases every year by your inflation rate, growing at your pre-retirement return rate), it solves for the starting monthly SIP amount needed so that your existing savings plus all future SIP contributions grow to exactly the required corpus by your retirement age.
Why use different return rates before and after retirement?
While you're working, you can typically afford a higher-risk, higher-return portfolio (e.g. 60-80% equity) since you have a long time horizon and ongoing income. After retirement, most people shift toward safer, more stable instruments (debt funds, fixed deposits, SCSS, annuities) since you're now depending on this corpus for income and can't easily recover from a market downturn. A 12% pre-retirement / 7% post-retirement split is a common conservative assumption.
What if I already have some retirement savings?
Enter your current retirement savings (PF, PPF, mutual funds, etc.) in the "Existing Retirement Savings" field. This amount is assumed to grow at your pre-retirement return rate until you retire, and is subtracted from the total corpus requirement before calculating how much additional monthly SIP you need.
How accurate is this projection?
This is a planning estimate, not a guarantee. Real inflation, investment returns, life expectancy, healthcare costs, and lifestyle changes will all differ from fixed assumptions. Treat the output as a starting target and revisit it every few years — especially after major life changes — using updated numbers. For inflation assumptions, see our Inflation Calculator.
What happens if the corpus runs out before life expectancy?
The calculator solves for the exact corpus that reaches zero in the year you hit your life expectancy — it doesn't build in any extra buffer. If you live longer than expected, or your post-retirement returns are lower than assumed, the corpus could be exhausted earlier. Many planners add a margin by entering a higher life expectancy (e.g. 85-90) or a slightly lower post-retirement return than they actually expect.
Why does the required SIP increase every year instead of staying fixed?
A fixed monthly SIP that never changes would lose ground to inflation over a 20-30 year horizon, since ₹10,000 invested today buys far less in real terms 25 years from now. By increasing the SIP every year at the same rate as inflation, the calculator keeps your contribution proportional to your rising income and expenses, which usually results in a lower starting SIP than a flat-SIP approach would require for the same target.
What do "Corpus Shortfall" and "Balance at Life Expectancy" mean?
"Corpus Shortfall" is the gap between the corpus you need and what your existing savings alone will grow to by retirement — this is the amount your step-up SIP is designed to close, and it shows "None" if your existing savings already cover the full corpus. "Balance at Life Expectancy" is the projected corpus left over at the end of the year-by-year table: it should be close to ₹0 if you invest exactly the required SIP, or positive if your existing savings (plus SIP, if any) exceed what's strictly needed.