Calculate how long your retirement savings will last and how much monthly income you can safely withdraw. Factor in Social Security, pensions, inflation, and investment returns to plan your retirement income strategy.
The most important question in retirement planning isn't "how much do I need to save?" but "how much can I sustainably spend each month once I retire?" These are different questions. The savings target depends on the spending plan; the spending plan depends on what your assets can support given how long you might live, what returns markets produce, and how inflation chips away at purchasing power.
The classic answer is the "4% rule" — withdraw 4% of your starting portfolio in the first year of retirement, then adjust the dollar amount upward for inflation each year. This rule, derived from the 1990s Trinity Study analyzing 30-year retirements, has very high historical success rates. A $1 million portfolio supports roughly $40,000 of year-1 withdrawal under the 4% rule, growing with inflation. Combined with Social Security ($24,000-$36,000/year for typical workers) and any pensions, total retirement income of $70,000-$100,000 is achievable for households with adequate savings.
This calculator projects how long your savings will last given your specific withdrawal rate, investment returns, and inflation assumptions. It accounts for non-portfolio income (Social Security, pensions) that reduce the withdrawal need. Use it to size the right withdrawal rate, stress-test your plan against different return scenarios, and identify whether longer-than-expected retirement creates shortfall risk. For early retirees with 40-50 year horizons, conventional 4% rules may be too aggressive — many planners suggest 3-3.5% withdrawal rates for very long retirements.
$750K portfolio. $4,000/mo desired ($48K/year). $2,000/mo SS ($24K/year). 5% return, 3% inflation, 30 years. Portfolio need: $24K/year initially, growing with inflation. Effective portfolio withdrawal rate year 1: 3.2%. Portfolio survives full 30 years with growing balance — Social Security carrying half the load makes the math much more comfortable. If SS is delayed to 70 (instead of 67), monthly benefit jumps to ~$2,480 — even more portfolio support.
Retire at 60, claim SS at 67. $1M portfolio. Need $50K/year for 7 gap years before SS, then $30K/year after SS starts (SS covers $20K). Years 1-7: withdraw $50K/year (5% withdrawal rate) Years 8+: withdraw $30K/year (3% effective rate against original portfolio) Higher initial withdrawal stresses the portfolio early, but the drop after SS starts gives long-term recovery. Sequence-of-returns risk in the early gap years is the main concern — bad markets in years 1-3 can permanently impair the plan. Many early retirees use a "cash bucket" of 2-3 years' expenses to ride out early-retirement market drops without selling investments at lows.
$300K portfolio. $4,000/mo desired ($48K/year). $1,800/mo SS. 5% return, 3% inflation. Portfolio need: $48K − $21.6K SS = $26.4K/year. Withdrawal rate: 8.8% — far above safe rates. Portfolio likely depletes around year 12-15. The plan is not sustainable for a 30-year retirement. Options: (1) reduce expenses to $36K/year ($14.4K from portfolio = 4.8% — still aggressive but more sustainable), (2) work part-time for 5-10 years to defer portfolio drawdown, (3) delay SS to 70 for higher monthly benefit, (4) move to lower cost-of-living area to reduce expense base. For households with inadequate savings approaching retirement, the gap is real and requires meaningful lifestyle adjustment. Wishing it away doesn't work.
Use this calculator within 5-10 years of planned retirement to size sustainable spending, immediately after retirement to confirm the plan still works, and annually thereafter to monitor portfolio performance vs plan.
Pair with retirement-savings (accumulation phase), social-security-benefit (the SS claiming decision), retirement-shortfall (gap analysis), FIRE-calculator (early retirement specifics), and life-expectancy (since longevity drives the math).
A key concept: sequence-of-returns risk. Bad markets in the first 5-10 years of retirement disproportionately damage long-term outcomes vs. bad markets later. A flexible withdrawal strategy that reduces spending in down years dramatically improves portfolio survival.
Project your retirement savings growth and see if you are on track.
Compare Social Security benefits by claiming age from 62 to 70.
Find out if you are saving enough for retirement and calculate your savings gap.
Compare taking a lump sum payout versus an annuity over time.
Estimate your 401(k) balance at retirement with employer matching and investment growth.
Compare Traditional vs Roth IRA growth and tax implications over time.
Total Monthly Income
$6,000
Withdrawal Rate
6.4%
Years Money Lasts
20
Ending Balance
$0
| Year | Withdrawal | Other Income | Growth | Balance |
|---|---|---|---|---|
| 1 | $48,000.00 | $24,000.00 | $37,500.00 | $739,500.00 |
| 2 | $49,440.00 | $24,000.00 | $36,975.00 | $727,035.00 |
| 3 | $50,923.20 | $24,000.00 | $36,351.75 | $712,463.55 |
| 4 | $52,450.90 | $24,000.00 | $35,623.18 | $695,635.83 |
| 5 | $54,024.42 | $24,000.00 | $34,781.79 | $676,393.20 |
| 6 | $55,645.16 | $24,000.00 | $33,819.66 | $654,567.70 |
| 7 | $57,314.51 | $24,000.00 | $32,728.39 | $629,981.58 |
| 8 | $59,033.95 | $24,000.00 | $31,499.08 | $602,446.71 |
| 9 | $60,804.96 | $24,000.00 | $30,122.34 | $571,764.08 |
| 10 | $62,629.11 | $24,000.00 | $28,588.20 | $537,723.18 |
| 11 | $64,507.99 | $24,000.00 | $26,886.16 | $500,101.35 |
| 12 | $66,443.23 | $24,000.00 | $25,005.07 | $458,663.19 |