The number most retirement calculators skip
Plenty of tools tell you what you will have at retirement. Far fewer tell you what happens next, which is the part that actually decides whether the plan works. A large balance and expensive tastes can run out faster than a modest balance and modest spending, and only the drawdown phase reveals it.
So this runs both phases. It accumulates to your retirement date, then draws down year by year with spending rising by inflation while the remaining balance keeps earning. If the money runs out before your planning age, it tells you the age it happens and how many years short you are — which is a far more useful prompt than a large number with no context.
Why spending is entered in today's money
Nobody knows what $60,000 of lifestyle will cost in 2051, but everyone knows what it costs now. So the input is in today's money and the tool inflates it to your retirement date before drawdown starts. At 2.5% over 25 years, $60,000 of spending becomes about $111,000 a year in the money of the day — and it keeps rising every year of retirement thereafter.
That escalation is what quietly breaks plans built on a flat withdrawal figure. A model that spends the same nominal amount every year for thirty years is describing a steadily shrinking standard of living, not a stable one.
Two returns, because retirement is not accumulation
The tool asks for a return while saving and a separate, usually lower, return in retirement. This reflects the common shift toward less volatile holdings as the horizon shortens: a portfolio you cannot afford to see fall 30% is generally not the portfolio you held at forty.
There is a deeper reason to treat the phases separately. While you are contributing, the order of good and bad years barely affects the final balance. Once you are withdrawing, it matters enormously — a bad run early in retirement forces selling into a falling market and can permanently damage a portfolio that would have survived the same returns in a different order. A constant-rate model like this one cannot capture that, so treat a plan that only just works as one that does not.
What is not included
Social Security, state pensions, workplace pensions, annuities and any other income in retirement are all excluded, and all of them push the answer in your favour — often substantially. Tax on withdrawals is also excluded and pushes the other way, with the size depending heavily on whether savings sit in pre-tax or post-tax accounts. Healthcare costs, which frequently rise faster than general inflation, are only captured to the extent you build them into the spending figure.
The output is arithmetic on your assumptions, not a forecast, and this is a subject where a professional who can see your whole position is worth the fee. The 401(k) calculator handles employer matching in the accumulation phase, and the investment calculator covers growth without the drawdown.
Frequently asked questions
Will my retirement savings last?
The tool answers that directly for your figures: it draws the balance down year by year with spending rising by inflation, and reports the age the money runs out if it does, along with how many years short that leaves you.
Why do I enter spending in today\u2019s money?
Because you know what your lifestyle costs now and not what it will cost decades ahead. The tool inflates it to your retirement date automatically \u2014 $60,000 today becomes roughly $111,000 a year after 25 years at 2.5%.
Why are there two different return rates?
Most people shift toward less volatile holdings as retirement approaches, so the return while saving and the return while drawing down are rarely the same. Separating them also reflects that the order of returns matters far more once you are withdrawing.
Does this include Social Security or a pension?
No. Any retirement income is excluded and would improve the picture, often substantially. Tax on withdrawals is also excluded and works the other way.