Calculate the retirement corpus needed to fund spending for any lifespan using inflation-adjusted present value math. Enter your retirement age and get needed corpus and funding gap instantly — no spreadsheet required.
Step 1. Enter your retirement age in the first field.
Step 2. Fill in life expectancy, annual spend to complete the required inputs.
Step 3. The calculator instantly shows Needed Corpus, Funding Gap, Survival Horizon based on the formula: Required Corpus = PMT×[(1−(1+r)^−n)/r]; r=(1+return)/(1+inflation)−1; n=retirement years; PMT=annual inflation-adjusted spend (PV of annuity formula).
With the default inputs loaded in the form, the calculator produces a starting result you can use as a baseline. Change one field at a time to compare a new scenario.
The Longevity Planning Calculator works by applying the formula: Required Corpus = PMT×[(1−(1+r)^−n)/r]; r=(1+return)/(1+inflation)−1; n=retirement years; PMT=annual inflation-adjusted spend (PV of annuity formula). Each input plays a distinct role — small changes to retirement age can shift needed corpus significantly, which is why running multiple scenarios before making a decision is valuable.
To use this calculator effectively, gather accurate values for Retirement Age, Life Expectancy, Annual Spend, Inflation. Estimates are fine for exploration, but the more precise your inputs, the more actionable the output. The calculator instantly returns Needed Corpus, Funding Gap, Survival Horizon, giving you a clear picture of where you stand.
This type of retirement calculation is commonly used in real planning scenarios — not just academic exercises. Whether you are comparing options, setting a target, or checking your current position, the Longevity Planning Calculator gives you a reliable number to work from. Always revisit the calculation if any input changes significantly.
It calculates needed corpus, funding gap, survival horizon using the formula Required Corpus = PMT×[(1−(1+r)^−n)/r]; r=(1+return)/(1+inflation)−1; n=retirement years; PMT=annual inflation-adjusted spend (PV of annuity formula). The inputs required are retirement age, life expectancy, annual spend, inflation.
You need: Retirement Age; Life Expectancy; Annual Spend; Inflation. Use accurate figures from your actual situation for the most useful result.
Results are mathematically precise given the inputs you provide. The formula used is: Required Corpus = PMT×[(1−(1+r)^−n)/r]; r=(1+return)/(1+inflation)−1; n=retirement years; PMT=annual inflation-adjusted spend (PV of annuity formula). Accuracy depends on how precise your input values are — estimates work for planning, but use exact figures for final decisions.
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Disclaimer: Results from this calculator are for informational and planning purposes only and do not constitute financial, legal, or professional advice. Always verify important calculations with a qualified professional.
