Savings Runway Calculator
Find out how long your savings or retirement fund will last based on your monthly withdrawal rate and expected rate of return.
Your savings will last
35 years, 11 months
Total withdrawn over that time: $215,459
Recommended Settings
Pro Tips
- •If your monthly withdrawal is less than or equal to what your balance earns in interest each month, your savings can last indefinitely - the balance never shrinks
- •Small changes in your assumed rate of return can shift the result by years, since compounding effects build up over long time horizons
- •This uses a fixed, steady rate of return for simplicity - real investment returns vary year to year, so treat this as a planning estimate, not a guarantee
- •Try a few different withdrawal amounts to see how much runway a small reduction in monthly spending can add
Most Popular
Many people test a 4% annual withdrawal rate, a common retirement planning rule of thumb
When to Use This Tool
Estimate how long a retirement account will support a given monthly withdrawal.
Check how long an emergency fund or lump sum will cover ongoing expenses.
See how adjusting your monthly withdrawal changes how long your money lasts.
Test a lower assumed return to see how your plan holds up in a weaker market.
How It Works
Convert your annual return rate into a monthly compounding rate
Check whether your monthly withdrawal is fully covered by the interest the balance earns each month - if so, the balance lasts indefinitely
Otherwise, solve the standard annuity depletion formula for the number of months until the balance reaches zero
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Frequently Asked Questions
What does it mean if my savings last 'indefinitely'?
It means your monthly withdrawal is smaller than or equal to the interest your balance earns each month at the assumed rate of return, so the principal never actually shrinks over time.
Does this account for inflation?
No, this calculates purely based on a fixed withdrawal amount and rate of return. If you want to account for rising costs over time, use a smaller effective withdrawal amount or a lower net rate of return to compensate.
Why does a small change in return rate make such a big difference?
Over long time horizons, compounding amplifies small differences in rate of return - a percentage point or two can change how long a balance lasts by years, especially near the break-even point where withdrawals roughly match interest earned.
Is this financial advice?
No, this is a general-purpose estimation tool based on a fixed rate of return assumption, not personalized financial or tax advice. Consult a financial advisor for retirement planning specific to your situation.