Savings Withdrawal Calculator
Find how long savings last with regular withdrawals.
Results update as you type.
How it works
If you have savings and withdraw a fixed amount each month, how long will the money last? This calculator tells you. You enter your current balance, the annual interest rate your savings earn, and your monthly withdrawal, and it returns how many months and years the balance will last before it runs out. The calculation accounts for the interest your remaining balance keeps earning while you draw it down, using the annuity formula solved for the number of periods. A crucial insight is the tipping point: if your monthly withdrawal is less than or equal to the interest your balance earns each month, you are only spending the interest, so the principal never shrinks and the money lasts indefinitely; the calculator reports this case as no depletion. Once withdrawals exceed the interest, the balance declines and eventually runs out, sooner with larger withdrawals or lower interest. This tool is valuable for retirement planning, deciding sustainable spending from a nest egg, and any situation where you draw down a lump sum over time. It complements the withdrawal-rate approach by showing the actual timeline for a chosen withdrawal amount. Note it assumes a constant interest rate and withdrawal and ignores inflation and taxes, which shorten how long money truly lasts in real terms. Enter your balance, rate, and monthly withdrawal to see how long your savings last.
Months = −ln(1 − balance × r / withdrawal) / ln(1 + r)
This solves the annuity formula for time: how many monthly withdrawals a balance supports while it continues to earn interest. If the monthly withdrawal is less than or equal to the interest the balance earns each month, the savings never deplete and last indefinitely, which the calculator reports as no depletion.
Source:Time value of money
We review all our tools from time to time to ensure accuracy.
Worked example
How to use this calculator
- 1
Enter your values
Enter current balance, annual interest rate and monthly withdrawal.
- 2
Adjust the options
Fine-tune any options to match your situation.
- 3
Read your result
Months until depleted updates instantly as you type — no button to press.
Frequently asked questions
How long will my savings last?
It depends on your balance, the interest it earns, and how much you withdraw each month. The calculator uses the annuity formula to find how many months the balance supports your withdrawals while still earning interest. Larger withdrawals or lower interest deplete the savings faster.
When do savings last indefinitely?
If your monthly withdrawal is less than or equal to the interest your balance earns each month, you are spending only the interest and the principal never shrinks, so the money lasts indefinitely. The calculator reports this as no depletion. Withdrawing more than the interest is what eventually exhausts the balance.
Does the interest rate really matter?
Yes. The interest your remaining balance earns extends how long it lasts, because it partially replenishes what you withdraw. A higher rate means your savings last considerably longer for the same withdrawal, and it can be the difference between depleting the balance and having it last forever if withdrawals are modest.
Does this account for inflation and taxes?
No. The calculator assumes a constant interest rate and a fixed nominal withdrawal, and it ignores inflation and taxes. In reality, inflation raises your spending needs over time and taxes reduce your net returns, so your savings will typically last a shorter time in real terms than this nominal estimate suggests.
How is this different from the 4% rule?
The 4 percent rule suggests a safe annual withdrawal as a percentage of your starting portfolio for a roughly 30-year horizon. This calculator instead takes a specific dollar withdrawal and interest rate and computes exactly how long the money lasts. Use the rule to set a sustainable rate and this tool to see the timeline for a chosen amount.