Retirement Calculator
Find out whether your savings will last through retirement, and what the gap is.
About Retirement Calculator
The calculator runs a two-phase projection. During accumulation, it compounds your existing savings and monthly contributions at the expected return rate. At retirement, it computes the present value of your desired income stream (inflation-adjusted) to find how large a nest egg you actually need. The difference is your surplus or shortfall — and the implied withdrawal rate tells you whether you're within the sustainable range the 4% rule describes.
Formulas
Nest egg at retirement
Future value = Current savings × (1 + monthly rate)^periods + Monthly contribution × ((1 + rate)^periods − 1) / rate
- PV_0
- Current savings
- PMT
- Monthly contribution
- r
- Monthly return rate (annual ÷ 12)
- n
- Months to retirement
Required nest egg (inflation-adjusted annuity)
Required nest egg = Monthly gap × (1 − (1 + real rate)^−n) / real rate
- PMT
- Monthly income gap (desired − other income)
- r_real
- (1 + withdrawal rate) / (1 + inflation rate) − 1
- n
- Months in retirement
Worked example
With the default values below, Retirement Calculator returns Projected Nest Egg of $1,015,810. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Current Ageaccepts 18–80
- 35
- Retirement Ageaccepts 40–85
- 65
- Life Expectancyaccepts 50–110
- 90
- Current Retirement Savingsminimum 0 $
- 50,000 $
- Monthly Contributionminimum 0 $
- 500 $
- Expected Annual Return (Accumulation)accepts 0–20
- 7
- Expected Annual Return (Withdrawal)accepts 0–15
- 5
- Desired Monthly Retirement Incomeminimum 0 $
- 4,000 $
- Other Monthly Income in Retirementminimum 0 $
- 1,500 $
- Inflation Rateaccepts 0–10
- 2.5
Results
- Projected Nest Egg
- $1,015,810
- Required Nest Egg
- $557,594
- Surplus / (Shortfall)Positive means you exceed the need; negative means a gap remains.
- $458,217
- Coverage RatioHow much of the required nest egg your projected savings cover.
- 182.2%
- Implied Withdrawal RateAnnual income from portfolio ÷ nest egg. 4% is the classic rule of thumb.
- 2.95%
- Monthly Portfolio Withdrawal
- $2,500
- Total Contributions
- $230,000
- Years to Retirement
- 30
- Years in Retirement
- 25
Step by step
- 1Years until retirement= 30 years
- 2Grow savings + contributions over accumulation phase= $1,015,810
- 3Income gap from portfolio (desired − other income)= $2,500/month
- 4Present value of income needed over retirement= $557,594
- 5Surplus at retirement= $458,217You're on track. Nest egg covers 182.2% of the need.
Assumptions and limits
- The result is derived only from the 10 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take tax into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
- Projections are illustrative only. Actual investment returns vary and are not guaranteed. Consult a financial advisor before making retirement planning decisions.
- This is an estimate for general information and not professional financial, tax or legal advice. See the full disclaimer for the limits that apply to this kind of calculator.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Guides that use this calculator
Projections are illustrative only. Actual investment returns vary and are not guaranteed. Consult a financial advisor before making retirement planning decisions.
Frequently Asked Questions
What is the 4% rule and how does it relate to this calculator?
The 4% rule states that withdrawing 4% of your portfolio annually has historically sustained 30-year retirements. This calculator shows your implied withdrawal rate so you can compare it to that benchmark. Above 5% is generally considered risky; below 3% is very conservative.
Why is the required nest egg different from monthly income × months?
Because your money keeps earning returns during withdrawal. The present-value formula accounts for continued growth, letting a smaller lump sum fund the same income stream. The inflation adjustment further reduces the required amount when returns exceed inflation.
Should I use a lower return for the withdrawal phase?
Yes — most advisors recommend a more conservative portfolio in retirement (e.g. 50/50 equities/bonds) to reduce sequence-of-returns risk. A 5% withdrawal-phase return is a reasonable default; feel free to adjust based on your planned asset allocation.
Does this account for Social Security?
Indirectly. Enter your expected Social Security benefit in 'Other Monthly Income'. The calculator subtracts it from your desired income, so only the gap is drawn from the portfolio.