Safe Withdrawal Rate Calculator: Annual Withdrawal as a Share of Portfolio
Work out your retirement withdrawal rate — annual withdrawal as a percentage of portfolio — and check it against the 4% rule, the most-cited benchmark for retirement sustainability.
Adjust the inputs and select Calculate for a full breakdown.
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | Withdrawal rate | Portfolio remaining share |
|---|---|---|
| $40k / $1M (4% rule) | 4.00% | 96.00% |
| $30k / $1M (3% safe) | 3.00% | 97.00% |
| $60k / $1.2M (5% aggressive) | 5.00% | 95.00% |
| $80k / $2.5M (3.2%) | 3.20% | 96.80% |
How This Calculator Works
Enter your planned annual withdrawal and total portfolio value. The calculator divides one by the other and multiplies by 100 to give the withdrawal rate, with the portfolio-remaining share shown alongside. Compare against the 4% rule: rates at or below 4% have historically sustained a 30-year retirement; higher rates raise the depletion risk.
The Formula
Part as a Percentage of a Whole
Part is the portion, Whole is the total it belongs to
Worked Example
A $40,000 annual withdrawal from a $1,000,000 portfolio is a 4% withdrawal rate — exactly the classic benchmark. The 4% rule (from the Trinity Study) found that a 4% initial withdrawal, adjusted for inflation each year, survived all historical 30-year periods in a balanced stock/bond portfolio. A 3% rate is very safe; a 5% rate carries meaningful depletion risk in poor market sequences.
Key Insight
The 4% rule is a starting benchmark, not a guarantee. It was derived from US historical returns and a 30-year horizon — early retirees (40-year+ horizons) often use 3% to 3.5% for safety, while flexible retirees who can cut spending in down markets can sustain 4.5% to 5%. Sequence-of-returns risk (poor returns early in retirement) is the real danger; the same average return delivered in a bad order can deplete a portfolio that a good order would sustain. Build in flexibility rather than treating any fixed rate as a promise.
Why 4% may be too aggressive for early retirees
Bengen's 4% study assumed 30-year retirement. Early retirees may have 40-60 year horizons. Modern research (Big ERN's Safe Withdrawal Rate Series): 4% rule's success rate drops dramatically for longer retirements. 30-year: ~95% success rate; 40-year: ~85%; 50-year: ~70%; 60-year: ~50%.
For 60-year retirement (FIRE at 30, dying at 90): conservative SWR is 3.0-3.25% rather than 4%. This requires 30-33× annual expenses ($1.65M for $50K spending) rather than 25× ($1.25M).
Sequence-of-returns risk: early retirement years dominate outcome. Poor returns in year 1-5 of retirement can permanently damage portfolio even if average returns are normal. The '4% rule' actually 'failed' in worst historical periods (1929 retirement; 1965 retirement) primarily due to bad early returns. For early retirees, planning for these scenarios via conservative WSR or 'flexible spending' approach is essential.
Mitigation strategies: (1) hold larger cash buffer in early retirement (3-5 years of expenses); (2) maintain flexibility to reduce spending in down markets; (3) consider part-time work (Coast FIRE/Barista FIRE) to reduce withdrawal need during bad market years.
CAPE-based dynamic SWR
Static SWR (always 4%) is simple but ignores starting valuations. Stock valuations at retirement start affect forward returns substantially. CAPE (Cyclically Adjusted P/E, Shiller's metric) is most reliable forward indicator.
Historical pattern: retirements starting at HIGH CAPE produce lower forward returns; retirements at LOW CAPE produce higher returns. 1929 (CAPE 31, very high) and 1965 (CAPE 23) — bad retirement starts. 1982 (CAPE 7, very low) — excellent retirement start.
Modern (2024) starting CAPE: ~34 — second-highest in history after 1999-2000. Implication for retirees starting now: forward returns likely lower than historical average; SWR should be more conservative than historical 4%.
Big ERN's CAPE-based SWR framework: SWR ~= 1.75% + (50% / current CAPE). At CAPE 34: SWR = 1.75 + 1.47 = 3.22%. At CAPE 20: SWR = 1.75 + 2.5 = 4.25%. At CAPE 10: SWR = 1.75 + 5 = 6.75%. The framework adjusts withdrawal for starting valuations.
Implication: 4% rule works in low-CAPE start; doesn't in high-CAPE start. 2024 retirees should target 3-3.5% withdrawal initially with increases if returns are strong. This requires more accumulation but provides higher safety margin.
Safe withdrawal rates by retirement horizon
Reference SWR by retirement length, historical analysis.
| Retirement length | Historical success at 4% | Recommended SWR | Notes |
|---|---|---|---|
| 20 years (traditional retirement) | ~99% | 5% | Higher than 4% works for short horizon |
| 30 years (Bengen study) | ~95% | 4% | Classic 4% rule |
| 40 years (early retirement) | ~85% | 3.5-3.75% | Longer horizon needs lower SWR |
| 50 years (early FIRE) | ~70% | 3.25-3.5% | |
| 60 years (FIRE at 30) | ~50% | 3.0-3.25% | Very conservative needed |
| High-CAPE start (>30) | Lower | Subtract 0.5% | Adjust down for high valuations |
Conservative SWR (3.0-3.5%) requires 28-33× annual expenses rather than 25× — substantial additional accumulation. The trade-off: 3-7 additional years of work to accumulate larger portfolio vs higher risk of running out of money in early retirement. Many early retirees opt for conservative SWR + maintain flexibility to reduce spending if needed.
Frequently Asked Questions
How is the withdrawal rate calculated?
Divide annual withdrawal by portfolio value, multiply by 100. $40,000 from a $1,000,000 portfolio is a 4% withdrawal rate.
What is the 4% rule?
A retirement guideline from the Trinity Study and William Bengen's research: withdrawing 4% of your portfolio in year one, then adjusting that dollar amount for inflation each year, historically sustained a 30-year retirement in a balanced (50/50 to 75/25 stock/bond) portfolio across all US historical periods.
Is 4% safe for early retirement?
Less so. The 4% rule assumed a 30-year horizon. Early retirees facing 40-to-50-year retirements often use 3% to 3.5% for safety. The longer the horizon, the lower the sustainable rate, because there's more time for a bad sequence to deplete the portfolio.
What is sequence-of-returns risk?
The danger that poor returns early in retirement deplete a portfolio that the same average returns in a different order would sustain. Withdrawing during a downturn locks in losses. It's why flexibility (reducing withdrawals in down years) dramatically improves sustainability.
Can I withdraw more than 4%?
With flexibility, yes. Retirees who can cut discretionary spending in down markets can often sustain 4.5% to 5%. Variable-withdrawal strategies (guardrails, percentage-of-portfolio) adapt to market conditions and typically allow higher average withdrawals than the fixed 4% rule while maintaining safety.
When is this calculator unreliable?
As long-term forward planning — assumes constant SWR over entire retirement. Modern best practice: maintain flexibility to reduce withdrawal in down markets, use CAPE-based starting SWR for current valuations, hold larger cash buffer in early retirement years. The '4% rule' is starting point for analysis, not guaranteed success — sequence-of-returns risk in first 5-10 years dominates long-term outcome.
References & Authoritative Sources
- William Bengen — Original 4% Study — Determining Withdrawal Rates Using Historical Data · consulted June 1, 2026 · Original 1994 SWR research
- Trinity University — Trinity Study — Trinity Study Update · consulted June 1, 2026 · Academic SWR research
- Early Retirement Now — Safe Withdrawal Rate Series — SWR Series Big ERN · consulted June 1, 2026 · Comprehensive contemporary SWR research
Related Calculators
Data Sources & Benchmarks
This calculator draws on 2 independent, dated sources.
Methodology & Review
Safe withdrawal rate (SWR) calculates sustainable annual withdrawal as percentage of starting portfolio balance, adjusted for inflation each subsequent year. Bengen's original 4% study (1994): 30-year retirement, 60% stocks / 40% bonds, withdraw 4% in year 1, inflation-adjust each subsequent year. Survived all U.S. historical 30-year periods 1926-1976. The calculator returns annual withdrawal amount. For early retirement (40-60 year horizons), modern research suggests 3.0-3.5% SWR. RELIABILITY: Reliable as historical-data-based SWR calculation. Less reliable for forward planning because (a) future returns may differ from historical; (b) sequence-of-returns risk in early retirement matters greatly; (c) inflation periods can require additional flexibility; (d) personal circumstances (longer life expectancy, health costs) may require lower withdrawal.
Updated