The Number Every Retiree Needs — Before the Money Runs Out
Retirement planning usually focuses on the wrong end of the problem: how much to save. But the question that actually keeps retirees up at night is the other one — once the paychecks stop, how many years will this pile of money cover my life? Spend too fast and the money dies before you do; spend too cautiously and you leave experiences on the table.
This free calculator answers that question directly. Enter your current savings, what you plan to withdraw each year, and the return you expect your investments to earn. You get the number of years (and months) your savings will last, the total you will withdraw over your lifetime, and a year-by-year table showing your balance shrinking — or, in the best case, the happy verdict that your savings never run out. So if you have been asking yourself, “How long will my retirement savings last?” — this is where you get the answer from your own numbers, not a rule of thumb.
How to Use This Calculator
- Enter your current retirement savings. The total nest egg you will start retirement with — 401(k), IRA, and other invested savings combined.
- Enter your annual withdrawal. What you expect to spend from savings each year. Be honest here: include housing, healthcare, travel, and a buffer for surprises.
- Enter your expected annual return. The average yearly growth of your investments after fees. A conservative 4–6% is typical for a balanced retiree portfolio.
- Tap Calculate. The headline shows how long your money lasts; below it you get total lifetime withdrawals, total growth earned, and the full year-by-year balance table.
- Test scenarios. Try a lower return or higher spending to stress-test your plan — the table updates instantly.
What "How Long Will My Savings Last" Really Means
Your savings are in a tug-of-war every year. On one side, investment growth adds money; on the other, your withdrawals take it away. As long as growth covers the withdrawal, the balance holds steady or grows. The moment withdrawals exceed growth, the balance starts falling — and a falling balance earns less growth next year, which accelerates the decline. That compounding-in-reverse is why spending just a little too much can shave many years off your plan.
This is the logic behind the famous 4% rule: withdrawing about 4% of your savings in the first year (then adjusting for inflation) has historically lasted 25–30 years for a balanced portfolio. On $500,000, that is $20,000 a year. Withdraw 8% ($40,000) and the same pile lasts roughly 20 years at 5% returns — the math is unforgiving, which is exactly why calculating it matters.
There is also a beautiful edge case: if your annual withdrawal is less than or equal to your savings times the return (for example, withdrawing $25,000 or less from $500,000 earning 5%), growth fully replaces what you spend, and your savings never run out. The calculator detects this and tells you so.
The Formula (With a Worked Example)
where r = annual return as a decimal.
Never runs out when: Withdrawal ≤ Savings × r
Worked example: $500,000 in savings, $40,000 withdrawn per year, 5% expected return.
- r = 0.05. Check the boundary: $500,000 × 0.05 = $25,000 < $40,000, so the money will eventually run out.
- Years = −log(1 − 500000 × 0.05 ÷ 40000) ÷ log(1.05) = −log(0.375) ÷ 0.04879 ≈ 20.1 years
- The calculator reports this as 20 years, 1 month, with $804,211 withdrawn in total and $304,211 of growth earned along the way.
Here is what the first five years look like:
| Year | Start balance | Growth (5%) | Withdrawn | End balance |
|---|---|---|---|---|
| 1 | $500,000 | $25,000 | $40,000 | $485,000 |
| 2 | $485,000 | $24,250 | $40,000 | $469,250 |
| 3 | $469,250 | $23,463 | $40,000 | $452,713 |
| 4 | $452,713 | $22,636 | $40,000 | $435,348 |
| 5 | $435,348 | $21,767 | $40,000 | $417,116 |
Notice the pattern: growth shrinks every year while the withdrawal stays fixed. That gap — $15,000 in year one, widening every year after — is the engine of depletion.
Sensitivity Check: How Your Withdrawal Rate Changes the Answer
No input moves the result like the withdrawal rate. Using the same $500,000 at 5%:
| Annual withdrawal | Rate of savings | How long it lasts |
|---|---|---|
| $20,000 | 4% | Never runs out |
| $25,000 | 5% | Never runs out |
| $30,000 | 6% | About 37 years |
| $35,000 | 7% | About 26 years |
| $40,000 | 8% | About 20 years |
| $50,000 | 10% | About 14 years |
The cliff is steep — and below the growth line ($25,000 here), the principal never shrinks. Spending less beats earning more.
Why Fixed Withdrawals Lose to Inflation
The calculator works in today's dollars, but your spending will not stay flat. At 2% inflation, $4,000 a month becomes about $5,384 within 15 years (4,000 × 1.0215). Meanwhile withdrawals that rise with prices while markets slump create sequence-of-returns risk: early losses plus rising withdrawals deepen the hole fast. Use inflation-adjusted withdrawals or a real return (nominal minus inflation), or the safety margin is fiction.
401(k)s, IRAs, and RMDs: Account Rules That Change the Math
Where savings live changes the net math. Traditional 401(k) and IRA withdrawals are taxed as ordinary income — a $40,000 withdrawal might spend like ~$32,000 after tax. Roth withdrawals are tax-free, and Roth IRAs have no lifetime required minimum distributions; traditional accounts force them from age 73, pushing withdrawals above your plan. Common drawdown order: taxable accounts first, traditional second, Roth last.
Limitations — Please Read
- Constant return assumed. Real markets do not deliver 5% every year; a bad sequence of returns early in retirement (sequence-of-returns risk) can shorten your runway significantly. Treat the result as a central estimate, not a promise.
- No inflation adjustment. The calculator works in today's dollars with a fixed annual withdrawal. If you raise withdrawals with inflation, the money lasts fewer years.
- Taxes not included. Withdrawals from traditional 401(k)s and IRAs are taxed as income — your spendable amount is less than the gross withdrawal.
- Not financial advice. This is an educational planning tool. For decisions involving your life savings, talk to a qualified financial advisor or fiduciary.
Tips to Make Your Savings Last Longer
- Trim the withdrawal rate first. Cutting spending by just 10% often adds more years than chasing an extra 1% of return — and it carries zero market risk.
- Keep a cash buffer. Holding 1–2 years of spending in cash means you never have to sell investments during a market crash.
- Delay Social Security if you can. Each year you wait (up to age 70) permanently increases your benefit, reducing what your savings must cover.
- Revisit the plan annually. Re-run your numbers every year with your actual balance. Small course corrections early beat desperate cuts late.
- Watch fees. A 1% annual fee on a portfolio earning 5% silently consumes a fifth of your growth — and years of longevity.
- Plan for healthcare. Medical costs are the most common budget-buster in retirement; build them into your annual withdrawal honestly.
More Financial Calculators
Frequently Asked Questions
How long will $500,000 last in retirement?
It depends on spending and returns. Withdrawing $40,000 a year at a 5% average return, $500,000 lasts about 20 years. Withdraw only $20,000 (the 4% rule) and it can last 30 years or more. Enter your own numbers in the calculator above.
What is the 4% rule?
A retirement guideline suggesting you withdraw 4% of your savings in the first year of retirement, then adjust that amount for inflation each year. Historically, this pace has lasted 25–30 years for a balanced stock-and-bond portfolio. It is a rule of thumb, not a guarantee.
When does retirement money never run out?
When your annual withdrawal is less than or equal to your savings times the return rate. For example, $500,000 earning 5% generates $25,000 a year in growth — withdraw $25,000 or less and the principal never shrinks. The calculator flags this case automatically.
What return should I assume for retirement planning?
Conservative planners use 4–6% for a balanced portfolio after fees and inflation. Using 8–10% (stock-market historical averages before inflation) overstates what a retiree's typically more conservative portfolio will earn.
Does this calculator account for inflation?
No — it uses a fixed annual withdrawal in today's dollars. In reality, rising prices mean you will likely withdraw more each year, which shortens how long the money lasts. Treat the result as an optimistic baseline.
What about Social Security and pensions?
They extend your runway by reducing what savings must cover. A simple approach: subtract your expected annual Social Security and pension income from your spending, then enter only the remainder as the annual withdrawal.
What happens if the market crashes early in my retirement?
This is called sequence-of-returns risk, and it is the biggest threat to the calculation. Large losses early on — while you are also withdrawing — permanently shrink the base that future growth builds on. A cash buffer and flexible spending are the standard defenses.
How can I make my retirement savings last longer?
Spend a little less (the highest-impact lever), delay Social Security to increase benefits, keep investment fees low, hold a cash buffer for downturns, and re-run your plan every year to catch drift early.
Is $750,000 enough to retire on?
Often, at a moderate withdrawal rate. Withdrawing 4% ($30,000/year) at 5% returns never exhausts the principal — it can last indefinitely. Actual mileage depends on spending, taxes, and Social Security.
Will $1 million last forever at $50,000 a year?
At 5% returns, yes — growth ($1,000,000 × 5% = $50,000) exactly replaces the withdrawal. At 4%, the same withdrawal drains it in about 41 years.
How long will my savings last in retirement?
It depends on three numbers: how much you have saved, how much you withdraw each year, and the return your investments earn. If your yearly withdrawal stays below what your savings earn, the money can last indefinitely. Withdraw faster than the balance grows and it runs out on a schedule you can calculate — enter your three numbers in the calculator above and it will show you the year-by-year path, not just a single guess.
How long will my IRA last?
An IRA lasts exactly as long as the math says any savings pot lasts: enter your IRA balance as the savings amount and your planned yearly withdrawal above, and the projection applies as-is. One IRA-specific wrinkle — once required minimum distributions (RMDs) begin in your seventies, the IRS sets a minimum you must withdraw each year whether you need the money or not, which can shorten the timeline the calculator shows. The account-rules section on this page explains how RMDs change the picture.