How to use this calculator
- Enter your current age and planned retirement age.
- Enter your current savings and the amount you can invest each month.
- Set an expected return and inflation rate — results show your retirement corpus, the 4%-rule monthly withdrawal, and its inflation-adjusted purchasing power.
How it works
Monthly compounding: balance = balance×(1+i) + contribution; withdrawal ≈ corpus×4% ÷ 12
The 4% rule comes from historical back-testing: withdrawing 4% of the portfolio in year one (then adjusting for inflation) has historically sustained a portfolio for 30+ years. Treat it as a starting point, not a guarantee.
Frequently asked questions
What is the 4% rule?
It comes from the Trinity Study: if you withdraw 4% of your portfolio in the first retirement year and adjust for inflation thereafter, a stock/bond portfolio has historically very likely lasted 30+ years. It's an empirical starting point, not a promise.
What return should I assume?
The further you are from retirement, the closer you can stay to long-run equity averages (5–8%). As retirement approaches, lower the assumption and shift gradually toward bonds and cash.
Why does inflation matter here?
One million in 30 years buys far less than one million today. The tool converts your projected corpus into today's money using the inflation rate you enter, so you can judge adequacy.
Does this include pensions or social security?
No — it models personal savings and investments only. If you expect a pension, mentally add its monthly income to the modeled withdrawal.
Disclaimer Results are for reference only and do not constitute financial, tax, or legal advice. Actual rates, returns, and fees depend on the terms of your financial institution.