Withdrawal runway calculator
See how long a starting balance lasts under explicit constant assumptions, including withdrawal timing, inflation increases and the final partial withdrawal.
Deterministic fixed-rate model only. No safe-withdrawal judgment, tax, fees, volatility, sequence risk, life expectancy, pension or guarantee.
Year-end balance path
| Year | Balance | Total withdrawn |
|---|---|---|
| 1 | $241,445.58 | $18,164.41 |
| 2 | $232,177.89 | $36,692.11 |
| 3 | $222,160.99 | $55,590.36 |
| 4 | $211,357.33 | $74,866.58 |
| 5 | $199,727.72 | $94,528.32 |
| 6 | $187,231.24 | $114,583.3 |
| 7 | $173,825.2 | $135,039.37 |
| 8 | $159,465.01 | $155,904.57 |
| 9 | $144,104.15 | $177,187.07 |
| 10 | $127,694.07 | $198,895.22 |
| 11 | $110,184.09 | $221,037.54 |
| 12 | $91,521.36 | $243,622.7 |
| 13 | $71,650.73 | $266,659.56 |
| 14 | $50,514.63 | $290,157.16 |
| 15 | $28,053.05 | $314,124.72 |
| 16 | $4,203.37 | $338,571.62 |
Included
- Monthly or annual withdrawals
- Beginning- or end-of-period timing
- Fixed return and withdrawal-inflation assumptions
- Final partial withdrawal and annual balance schedule
Not included
- Safe-withdrawal-rate or retirement-adequacy advice
- Tax, fees, pension, life expectancy or investment mix
- Volatility, sequence risk or guarantees
What this means
Each period applies the withdrawal and return in the selected order. The next withdrawal then changes by the fixed inflation assumption.
The simulation stops after 200 years. A balance that remains is reported only as not depleted within that window—not perpetual, safe or adequate.
Formula & worked example
beginning timing: withdraw, then apply periodic return end timing: apply periodic return, then withdraw next withdrawal = current withdrawal × periodic inflation factor
$1,200 balance and $100 monthly withdrawal with zero return and inflation
- Timing
- Beginning of month
- Periods
- 12
The balance is depleted by a final $100 withdrawal in month 12.
How this calculation works
The calculation follows the formulas, definitions and assumptions explained on this page. The references below support the method and any stated boundaries.
Official sources
- OpenStax — annuities — Periodic cash-flow timing and deterministic drawdown arithmetic