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Savings withdrawal calculator

See how long a savings balance lasts with monthly withdrawals, or find the largest monthly withdrawal that lasts for the months you choose. Interest, yearly increases and the month the money runs out are shown in a full schedule.

Your result

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How to use Savings withdrawal calculator
  1. Enter the starting balance, the yearly interest or return and the number of months.
  2. Choose whether to test a withdrawal or find the largest one that lasts.
  3. Enter the monthly withdrawal, or the balance you want to keep at the end.
  4. Choose the withdrawal timing, how often interest is credited and any yearly increase, then review and download the JSON report or the monthly CSV.

Useful next steps

Method

The balance runs month by month. Interest accrues on the balance at the yearly rate divided by 12, rounded to the cent, and is credited at the end of each credit period. Withdrawals come out at the start or end of each month and rise every 12 months by your yearly increase. A withdrawal that would empty the account first receives the interest accrued so far; if it still cannot be paid in full, the account is depleted that month and the shortfall is shown.

Sustainable withdrawal

In the second mode the tool searches whole cents for the largest first-year withdrawal that is paid in full every month and leaves at least your target balance. It is the exact ledger version of the annuity relation behind the spreadsheet PV and PMT functions (Microsoft Support, PV function, checked 16 October 2026); one cent more falls short.

Assumptions and limits

The same return is applied every month. Real returns vary, and the order of good and bad years can change the outcome. Taxes, inflation and fees are not included. This is a calculation from your own numbers, not financial or retirement advice.