Retirement Corpus Calculator

The classic rule of thumb is 25× your annual post-retirement expenses (the "4% rule" inverted) — meaning a corpus that, withdrawn at 4% per year, lasts roughly 30 years through historical market scenarios. For an Indian household spending ₹6 lakh/year today (₹50k/month), the today's-rupee target is ₹1.5 crore. But that's in today's rupees — by retirement at age 60 (say 25 years from now) at 6% general inflation, the same lifestyle costs ₹2.6 lakh/month, and the corpus needed is roughly ₹6.4 crore in retirement-start rupees. Most Indian planners use 25–33× the inflated expense as the corpus target, which builds an additional buffer for medical costs (which inflate at 11–14% — well above general CPI).

The 4% rule comes from a 1994 US study (Bengen) showing that a 60/40 stock-bond portfolio could sustain a 4%-of-initial-balance withdrawal, inflation-adjusted, for 30 years across historical markets without depleting. In India, the picture is more nuanced. Indian equity returns have been higher (12–14% long-run vs ~10% US), but inflation has been higher too (6–7% vs ~3% US). Real returns net out roughly similar (5–7% in both markets). A 3.5–4% withdrawal rate is reasonable for Indian retirees with a 60–70% equity allocation in the early retirement years; lifelong post-retirement allocation needs to stay equity-heavy to outrun inflation, which is the dominant risk over 25–30 retirement years.

Two inflation rates matter and they're different. Pre-retirement (accumulation phase): use 6–7% general CPI to inflate your today's-rupee expenses to retirement-start rupees. Post-retirement (withdrawal phase): assume 7–8% blended inflation to account for medical-cost inflation (11–14% historical) being a larger share of senior spending. Build the corpus to cover the inflated expenses through the entire retirement window — a corpus that funds expenses at year 1 but doesn't grow with inflation through years 20–30 fails in real terms. The "25× annual expense" multiplier already builds in some inflation cushion if used against inflated retirement-start expenses; use 30–33× for a more conservative plan.

In your first earning year. The compounding gap between starting at 25 and starting at 35 is staggering: a ₹10,000/month SIP from age 25 to 60 at 12% builds roughly ₹6.5 crore; the same SIP from age 35 to 60 builds roughly ₹1.9 crore — same monthly amount, 10 years earlier, 3.4× the corpus. If you're later than 25, start now anyway; the comparison is to starting later still, not to the impossible "what if I'd started earlier." A 10% annual step-up on the SIP compensates for late starts by letting growing salary close some of the gap.

These three tax-advantaged instruments form the secure base of most Indian retirement plans. (1) EPF — 8.25% tax-free for FY26, mandatory for salaried at organisations with 20+ employees; over a 30-year career a steady EPF builds roughly ₹1.5–2.5 crore at typical contribution rates. (2) NPS Tier 1 — additional ₹50,000 deduction under 80CCD(1B); 75% equity / 25% debt under the auto-choice option for under-35s; locks until 60 with mandatory 40% annuitisation at maturity. (3) PPF — 7.10% tax-free, ₹1.5L/year, 15-year lock-in (extendable); good for tax-saving + secure base. Equity SIPs supplement these for the additional inflation-beating corpus needed. A typical balanced retirement plan: EPF + PPF + NPS provide 40–60% of corpus; equity SIPs provide the other 40–60%.

Partial annuitisation is usually right, but not 100%. NPS mandates 40% annuitisation at maturity; voluntarily annuitising more than that locks the funds permanently and forfeits flexibility, while Indian annuity products typically pay 5.5–7% (taxable) — meaningfully below diversified-equity expected returns. Pragmatic approach: keep 30–50% of the corpus annuitised or in guaranteed-income instruments (NPS annuity + Senior Citizen Savings Scheme + RBI Floating Rate Bonds) to cover essential expenses with certainty; keep the rest in a growth bucket (large-cap equity + balanced advantage funds) drawn down via Systematic Withdrawal Plan (SWP) at a sustainable rate. This split protects against both longevity risk (annuity covers it) and inflation risk (equity outpaces it).

It uses the goal-SIP engine — given a target corpus, expected return rate, and years to retirement, it solves for the monthly SIP needed. The target you enter should be the corpus you want available at retirement, in retirement-start rupees (with the inflation toggle off) or in today's rupees (with the toggle on, which inflates internally). For sizing the target itself: a useful starting heuristic is 25–33× your inflated annual retirement expenses. The companion Goal Inflation Calculator does the today-to-retirement-rupees conversion; pass the inflated number back here to size the SIP.

Three workable adjustments. (1) Start with a smaller SIP and step it up annually — a 10% annual step-up on ₹10,000 over 30 years builds nearly as much corpus as a flat ₹35,000 SIP. Use the step-up SIP calculator to size this. (2) Stretch the retirement age — moving from 55 to 60 buys 5 more years of accumulation and cuts the required monthly SIP by roughly 35%. (3) Plan for a lower-cost retirement location — moving from a metro to a tier-2 city in retirement can cut expenses by 40–50%, which dramatically shrinks the corpus needed. Hybrid strategies (work part-time post 60, draw a smaller corpus over fewer years) also bridge gaps.