ToolPetal
Retirement corpus calculator
- Runs on your device
- Nothing uploaded
- Free, no sign-up
| Step | Value |
|---|
Timeline: today → retirement → corpus
age / spend
inflate spend
corpus ÷ rr
Not tax or investment advice. Inflation and return rates are assumptions you can edit. The corpus is a real-return perpetuity, not a guarantee of lifestyle or lifespan.
Timeline: years to retirement → spend → corpus
Read the model left to right, not as a single magic number.
- Years to retire
n = retirement age − current age(defaults 60 − 30 = 30). - Annual spend today = monthly expenses × 12 (default 50,000 × 12 = Rs 6,00,000).
- Spend at retirement = that amount ×
(1 + inflation)^n≈ Rs 34,46,095 at 6% for 30 years. - Real return
rr = (1 + expected return) / (1 + inflation) − 1. - Corpus needed (when rr > 0) ≈ spend-at-retirement ÷ rr: a perpetuity that keeps real spending. Existing savings grow at the pre-retirement return for n years; surplus/shortfall = FV(savings) − corpus.
With defaults (7% post-retirement return, 6% inflation), rr ≈ 0.9434% and corpus ≈ Rs 36.5 crore. That headline is what a thin real-return perpetuity implies, not a personalized plan. Not investment advice. Disclaimer.
Why inflation matters on this page
Inflation does two jobs: it inflates today’s spend to retirement, and it shrinks the real return that funds the perpetuity. Raising inflation (or cutting expected return) moves both levers against you. The page does not model SIP top-ups during accumulation: grow a contribution schedule with the SIP or compound interest tools, then paste the projected nest egg into Existing savings.
Sensitivity: what if return is 1% lower?
Hold defaults except post-retirement expected return.
| Expected return | Real return rr | Corpus (spend ÷ rr) |
|---|---|---|
| 7% (default) | ≈ 0.9434% | ≈ Rs 36.53 crore |
| 6% (1% lower) | ≈ 0% (return = inflation) | No finite perpetuity: model needs return > inflation |
A one-point drop that erases the real-return gap is not a small tweak; under this teaching model the corpus diverges. Stress-test with a pessimistic case (higher inflation, lower return), a base case, and an optimistic case: the spread is the message, not any single rupee figure. No mortality table, taxes on withdrawals, fees, or sequence-of-returns risk.
FAQ
What does this retirement corpus calculator estimate?
It estimates the nest egg you would need on the day you retire so that annual spending, already inflated from today's monthly expenses, can continue in real terms. It also grows any existing savings to that date and shows the surplus or shortfall versus that corpus.
What formula does the retirement corpus calculator use?
Years to retire n = retirement age minus current age. Annual spend today is monthly expenses times 12. Spend at retirement is that amount times (1 + inflation)^n. Real return rr is (1 + expected return) / (1 + inflation) minus 1. If rr is positive, corpus needed is spend-at-retirement divided by rr: a perpetuity that keeps real spending. Existing savings grow at the pre-retirement return for n years. Inflation and return rates are assumptions you can edit.
Is this financial or tax advice?
No. This is a browser-only estimate using a simple real-return perpetuity. It is not tax advice, investment advice, or a plan. Actual needs depend on lifespan, taxes, fees, sequence of returns, and spending that is not constant in real terms.
Are my numbers uploaded?
No. Ages, expenses, rates, and the corpus math run in your browser. Nothing is sent to ToolPetal.