4% Rule Retirement Calculator

Simulate the Trinity Study / Bengen withdrawal protocol: fixed initial withdrawal rate adjusted for inflation each year. See whether your portfolio survives the planning horizon.

Last reviewed by Vanta Calc editorial

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Result

Plan outcome

$2,064,313 after 30 years

This calculator uses nominal returns + a separate inflation input. The Coast FIRE and FI Timeline calculators use real (inflation-adjusted) returns instead.

How the simulation runs

Year-1 withdrawal: $1,000,000 × 4.0% = $40,000
Each subsequent year, withdrawal grows by inflation (3.0%).
Portfolio grows at nominal return (7.0%) on the post-withdrawal balance.
Year-30 withdrawal: $94,263 (purchasing power equivalent to year-1).
Final nominal balance: $2,064,313 (real / today's dollars: $850,470).
Total withdrawn over 30 years: $1,903,017.

Summary

Plan outcomeSurvives 30 years
Year-1 withdrawal$40,000
Year-30 withdrawal$94,263
Ending balance (nominal)$2,064,313
Ending balance (real)$850,470
Total withdrawn$1,903,017
Initial portfolio$1,000,000
Real return4.00%

Year-by-year drawdown

YearStart balanceWithdrawalGrowthEnd balanceEnd (real)
1$1,000,000−$40,000+$67,200$1,027,200$997,282
2$1,027,200−$41,200+$69,020$1,055,020$994,458
3$1,055,020−$42,436+$70,881$1,083,465$991,524
4$1,083,465−$43,709+$72,783$1,112,539$988,476
5$1,112,539−$45,020+$74,726$1,142,245$985,310
6$1,142,245−$46,371+$76,711$1,172,585$982,021
7$1,172,585−$47,762+$78,738$1,203,560$978,605
8$1,203,560−$49,195+$80,806$1,235,171$975,055
9$1,235,171−$50,671+$82,915$1,267,415$971,368
10$1,267,415−$52,191+$85,066$1,300,290$967,538
11$1,300,290−$53,757+$87,257$1,333,791$963,559
12$1,333,791−$55,369+$89,489$1,367,911$959,425
13$1,367,911−$57,030+$91,762$1,402,642$955,131
14$1,402,642−$58,741+$94,073$1,437,974$950,670
15$1,437,974−$60,504+$96,423$1,473,893$946,036
16$1,473,893−$62,319+$98,810$1,510,384$941,222
17$1,510,384−$64,188+$101,234$1,547,430$936,221
18$1,547,430−$66,114+$103,692$1,585,008$931,025
19$1,585,008−$68,097+$106,184$1,623,095$925,628
20$1,623,095−$70,140+$108,707$1,661,661$920,021
21$1,661,661−$72,244+$111,259$1,700,676$914,197
22$1,700,676−$74,412+$113,838$1,740,103$908,146
23$1,740,103−$76,644+$116,442$1,779,900$901,861
24$1,779,900−$78,943+$119,067$1,820,024$895,331
25$1,820,024−$81,312+$121,710$1,860,422$888,548
26$1,860,422−$83,751+$124,367$1,901,038$881,501
27$1,901,038−$86,264+$127,034$1,941,809$874,181
28$1,941,809−$88,852+$129,707$1,982,664$866,576
29$1,982,664−$91,517+$132,380$2,023,527$858,676
30$2,023,527−$94,263+$135,049$2,064,313$850,470
yearstartBalancewithdrawalgrowthendBalancerealEndBalance
1100000040000672001027200997281.55
2102720041200690201055020994457.54
310550204243670880.881083464.88991523.85
41083464.8843709.0872782.911112538.71988476.23
51112538.7145020.3574726.281142244.64985310.26
61142244.6446370.9676711.161172584.83982021.34
71172584.8347762.0978737.591203560.33978604.69
81203560.3349194.9580805.581235170.95975055.36
91235170.9550670.882915.011267415.16971368.19
101267415.1652190.9385065.71300289.93967537.83
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Calculation Complete

The 4% rule with inflation adjustment is the canonical safe-withdrawal protocol from the Trinity Study (Cooley, Hubbard, Walz 1998) and Bengen (1994). You withdraw a fixed initial percentage in year one, then increase the *dollar* amount by inflation each subsequent year — keeping your real (purchasing-power) spending flat. This calculator simulates the protocol year by year so you can see whether a given portfolio, withdrawal rate, return, and inflation assumption survives your planning horizon.

Enter your starting portfolio, the initial withdrawal rate (4% is the Trinity Study default), expected nominal return on the portfolio, expected inflation, and the planning horizon in years. The result shows whether the portfolio survives, the year-by-year balances, your year-1 and year-N withdrawals (and the year-N withdrawal in real terms), and the ending balance in both nominal and today-dollar terms. Run alternate scenarios by adjusting the rate or horizon — early retirees with 40+ year horizons typically need 3.25-3.5% to maintain the same survival probability.

Examples

$1M, 4% initial, 7% return, 3% inflation, 30 years

Year-1 withdrawal $40,000. Year-30 withdrawal ~$94,000 nominal (still ~$40k in today's dollars). Ending balance nominal ~$2.4M, real ~$1M — the portfolio more than survives, ending with roughly its starting purchasing power intact. The classic Trinity Study result.

Same inputs, 5% initial withdrawal

Year-1 $50,000. Year-30 ~$117k nominal. Portfolio survives but ends much smaller in real terms (~$300k). 5% leaves much less margin for sequence-of-returns risk.

$1M, 4%, 5% return, 3% inflation, 40 years

Lower return + longer horizon = harder. Portfolio exhausted around year 30-32. This is why early retirees with 40+ year plans typically use 3.25-3.5% rather than 4%.

Frequently Asked Questions

Why does the withdrawal grow with inflation?
The 4% rule's purpose is to preserve real purchasing power, not the nominal dollar amount. If your year-1 withdrawal of $40,000 stayed flat for 30 years at 3% inflation, by year 30 it would buy what $16,500 buys today. Inflating the withdrawal each year keeps your real spending constant.
What is sequence-of-returns risk?
The risk that bad returns happen early in retirement, when the portfolio is largest and withdrawals are biting hardest. A 30-year sequence with the same average return survives at very different rates depending on whether the bad years come first or last. The Trinity Study found 4% has roughly a 95% survival rate across historical 30-year windows; the 5% who fail are dominated by retirees who started in 1929, 1965-1969, or 2000.
Should I use real or nominal returns here?
This calculator uses *nominal* return (matching the original Trinity Study presentation). Inflation is a separate input, and the inflation-adjusted ending balance is shown separately. If you have only a real return number, set inflation to 0% and use the real return as "expected return" — but the year-N withdrawal will then no longer grow.
Is 4% safe for early retirement?
Less safe than for a 30-year window. The Trinity Study used 30-year retirements; for 40-year horizons (early retirement at 50, expecting to live to 90+), the safe rate drops to roughly 3.25-3.5% to maintain a similar survival probability. Use this calculator with a longer horizon to see the difference.
What about taxes?
Not modelled directly — build them into your "annual withdrawal" by inflating the rate. If you need $40,000 to live on after taxes and you pay 15% effective on withdrawals, withdraw $47,059 / year, which on a $1M portfolio is a 4.7% rate.
Does the 4% rule include Social Security?
No — it assumes the portfolio is the sole income source. If you expect Social Security, a pension, rental income, or part-time work, reduce your "annual withdrawal" need by those inflows; the portfolio only has to fund the gap.

Sources

  1. Bengen, W. P. (1994). "Determining Withdrawal Rates Using Historical Data." — Journal of Financial Planning
  2. Cooley, P. L., Hubbard, C. M., Walz, D. T. (1998). "Retirement Savings: Choosing a Withdrawal Rate That Is Sustainable." — AAII Journal — the "Trinity Study"
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Quick Tips

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Did you know?
Calculators are estimates. Consult professionals for critical decisions.