How to use this calculator
- Enter starting fund, nominal annual rate (%), monthly periods.
- Choose a display currency, then select Calculate. Results also update after a brief pause while you edit.
- Read the result with the assumptions below. Export details or save a second scenario to compare your choices.
Formula and method
Assumptions and limitations
A constant nominal monthly return and end-of-month withdrawals are assumed. This is mathematical depletion, not a safe-withdrawal recommendation.
Worked example
A 12,000 fund at 0%, withdrawn over 12 months, provides 1,000 monthly and ends at zero.
What the result means
Find a constant monthly withdrawal that exhausts a modeled fund over a fixed period.
Common questions
How is the calculation performed?
Level withdrawal = fund / present-value annuity factor using monthly return; simulate end-of-month growth and withdrawals until the chosen final month.
What does the model leave out?
A constant nominal monthly return and end-of-month withdrawals are assumed. This is mathematical depletion, not a safe-withdrawal recommendation.
Methodology and transparency
Calculation specification reviewed on 2026-10-14. Mathematical implementation is tested against independent reference fixtures. This does not imply review by a licensed financial professional. Read the testing and precision policy.