Retirement Calculator
Find out whether your savings will last through retirement, and what the gap is.
Inputs
Used to compute how many years the nest egg must last.
Typical broad-market equity assumption before fees.
Lower than accumulation because portfolios are usually de-risked in retirement.
Social Security, pension, part-time work, etc.
Projected Nest Egg
$1,015,810
Required Nest Egg
$557,594
Surplus / (Shortfall)
$458,217
Positive means you exceed the need; negative means a gap remains.
Coverage Ratio
182.2%
How much of the required nest egg your projected savings cover.
Implied Withdrawal Rate
2.95%
Annual income from portfolio ÷ nest egg. 4% is the classic rule of thumb.
Monthly Portfolio Withdrawal
$2,500
Total Contributions
$230,000
Years to Retirement
30
Years in Retirement
25
Step by step
Years until retirement
65 − 35
= 30 years
Grow savings + contributions over accumulation phase
FV($50,000, $500/mo, 7%/yr, 30 yrs)
= $1,015,810
Income gap from portfolio (desired − other income)
$4,000 − $1,500
= $2,500/month
Present value of income needed over retirement
PV($2,500/mo, 5% real, 25 yrs)
= $557,594
Surplus at retirement
$1,015,810 − $557,594
= $458,217
You're on track. Nest egg covers 182.2% of the need.
How it works
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
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.