Retirement Corpus Calculator
Plan how much you need to save for a comfortable retirement
About the Retirement Corpus Calculator
The Retirement Corpus Calculator helps you estimate how much money you need to accumulate by the time you retire so you can maintain your desired lifestyle without relying on employment income. It accounts for inflation (which increases your future expenses), the return your corpus earns during retirement, and how long you expect to live after stopping work. Use Age-Range Phases to model realistic spending patterns — for example, higher travel expenses in early retirement and lower expenses later.
How to Use
- Enter your current age, the age you plan to retire, and your expected life expectancy.
- Choose Single Amount for a fixed monthly expense, or Age-Range Phases to define different spending at different life stages.
- For phases: the first phase starts at retirement age (auto-filled). Click + Add Phase to add more transitions (e.g., age 70 with a different amount).
- Set the expected inflation and return rates, add any existing savings, then click Calculate.
Formula Used
For multi-phase mode, each phase's corpus is discounted back to the retirement date at the nominal return rate and summed. The math is exact: each phase's allocation grows independently during earlier phases and depletes during its own phase.
Understanding Your Results
Frequently Asked Questions
How much do I need to retire?
A widely-used rule is 25× your annual expenses (the inverse of the 4% withdrawal rule). If you spend $40,000/year in retirement, target a $1,000,000 corpus. For higher confidence, plan for 28–33×.
What is a safe withdrawal rate?
The classic Trinity Study suggests 4% per year (adjusted for inflation) historically lasts 30+ years for a 60/40 stock/bond portfolio in most countries. Recent research suggests 3–3.5% is safer for early retirees or longer horizons.
When should I start saving for retirement?
As early as possible. Saving $300/month from age 25 at 8% returns yields ~$1M by 65; starting at 35 yields only ~$450k. The first decade matters more than any other because of compounding.
How does inflation affect my retirement corpus?
At 3% inflation, $1 today buys what $0.55 will in 20 years and $0.41 in 30 years. Always plan in real (inflation-adjusted) terms — assume your corpus grows at "return rate minus inflation" to estimate purchasing power.
Why use age-range expense phases?
Real retirement spending isn't flat. Early retirees often spend more on travel and activities; later years typically see lower discretionary spending but higher healthcare costs. Modelling distinct phases gives a more accurate corpus target than a single average.
Important Note
Retirement planning involves many variables — healthcare costs, lifestyle changes, tax implications, and unexpected events — that this calculator cannot fully model. A safe withdrawal rate of 3–4% of corpus per year is a common rule of thumb. We strongly recommend consulting a certified financial planner to build a personalised retirement strategy.