How Long Will My Money Last Calculator – Free Guide

If you type how long will my money last calculator into Google, you already know the real question behind it. Will your savings survive as long as you do? This tool sits at the center of retirement planning. Yet most articles repeat the same shallow definition without showing the math or comparing the calculators people actually use, such as Fidelity, Bankrate, NerdWallet, CalcXML, and Mutual of Omaha. Without answering the exact dollar scenarios readers search for, like whether $750,000 lasts through retirement at 62 or whether $2 million is enough at 40. This guide covers all of it, from the formula behind the number to the mistakes that quietly make these tools too optimistic.

What a How Long Will My Money Last Calculator Actually Calculates

A how long will my money last calculator is a reverse annuity tool. Instead of asking how much you need to save to reach a goal, it starts with the balance you already have and works backward to show how many years that balance can fund a withdrawal before it reaches zero.

This makes it different from a how much do I need to retire calculator, which solves for the required balance given a target income. The how long will my money last version flips the question, and it is the more useful tool once you already have savings and want to test whether your current withdrawal plan holds up.

If you have not worked out your target balance yet, this retirement calculator is a useful first step before you test withdrawal scenarios here.

Every version of this calculator, whether from Fidelity, Bankrate, or a simpler tool such as CalcXML, needs the same core inputs:

• Current account balance

• Planned withdrawal amount, monthly or annual

• Expected annual rate of return on the remaining balance

• Expected inflation rate, if withdrawals should rise each year

• Tax treatment of the withdrawals, since a traditional IRA withdrawal is taxed differently than a Roth withdrawal

The output is a number of years and months until depletion, or, when your rate of return exceeds your withdrawal rate, a message telling you the balance never runs out under the stated assumptions.

The Formula Behind the Calculator

You do not need the calculator to check the math. The number of periods your money lasts, assuming a constant withdrawal and constant return, comes from the present value of an annuity formula solved for time: n equals the negative natural log of one minus r times PV divided by PMT, divided by the natural log of one plus r. PV is your starting balance, PMT is your periodic withdrawal, and r is your periodic rate of return.

Example. You retire with $500,000, withdraw $2,500 monthly, and expect a 5 percent annual return, or about 0.4167 percent monthly. That produces roughly 349 months, close to 29 years. The withdrawal works out to 6 percent annually, above the traditional 4 percent guideline, and the math confirms the account draws down within a normal retirement length rather than lasting indefinitely.

One threshold matters most. If your planned withdrawal is less than or equal to your balance multiplied by your rate of return, your money never runs out mathematically, because you are only spending growth, not principal.

How to Use the Calculator Correctly

1. Enter your real balance, not your target balance.

2. Decide whether your withdrawal figure is gross or net of tax, since entering an after-tax number into a pre-tax field makes the result overly optimistic.

3. Choose a rate of return that reflects your actual portfolio net of fees, not a generic market average.

4. Set an inflation rate, typically 2.5 to 3.5 percent based on long-run averages, so spending power stays constant rather than shrinking.

5. Add other income, such as Social Security or a pension, as a separate input rather than folding it into your withdrawal number.

6. Run the calculation twice, once at your expected return and once two to three points lower, to see how sensitive the timeline is to a weaker market.

If you want to model portfolio growth in more detail before settling on a return assumption, an investment calculator lets you test different contribution and growth scenarios first.

Key Variables That Change Your Answer More Than You Think

Withdrawal Rate and the 4 Percent Rule

The 4 percent rule, from the 1994 Trinity Study, suggests withdrawing 4 percent in year one and adjusting for inflation each year after, with historically strong odds of lasting 30 years. Raise that to 5 or 6 percent and success rates drop sharply, especially for a retirement that begins during a downturn. A calculator lets you test rates above and below 4 percent instantly, which is more useful than relying on the rule alone.

Inflation

Skipping inflation is the most common reason a calculator overstates how long money lasts. A $4,000 monthly withdrawal today needs to become roughly $5,375 in fifteen years at 2 percent average inflation just to buy the same goods.

Taxes

A traditional 401k or IRA withdrawal counts as ordinary income, so a $40,000 withdrawal might net $33,000 or less after tax. A Roth withdrawal is generally tax-free once the account meets holding requirements, so calculators that separate account types by tax treatment produce more honest results.

Sequence of Returns Risk

Two retirees with identical average returns over 30 years can end up in very different places if the order of those returns differs. A market drop in the first five years of retirement, while still withdrawing a fixed amount, depletes an account faster than the same drop near the end. A cash buffer of one to two years of expenses is a common defense.

Comparing the Major How Long Will My Money Last Calculators

All six calculators solve the same formula shown above, but differ in the assumptions they let you control. If you want a fast, directional number, a simple tool works fine. If you want a number to actually plan around, choose one that separates withdrawals, taxes, and other income rather than combining them into a single field.

Real Scenarios People Actually Search For

How Long Will $750,000 Last in Retirement at 62

Using the 4 percent guideline, $750,000 supports about $30,000 in year one, adjusted for inflation, which historically lasts about 30 years, taking a 62-year-old to age 92. Raise withdrawals to 5 percent, and the same balance in a moderate portfolio typically lasts closer to 22 to 25 years. Adding Social Security reduces the withdrawal needed from the portfolio and extends the runway.

Is $2 Million Enough to Retire at 40

At 40, a retirement needs to fund 50 or more years, which changes the math. A 4 percent withdrawal on $2 million provides $80,000 in year one, but a 4 percent rate has a lower historical success probability over 50 years than over the standard 30-year horizon it was built for. Most planners suggest an early retiree use 3 to 3.5 percent instead, lowering first-year income to $60,000 to $70,000 but meaningfully raising the odds the money lasts.

Common Mistakes People Make With These Calculators

• Entering current spending as the withdrawal amount without accounting for healthcare costs rising faster than general inflation later in retirement.

• Leaving the inflation field at zero, which makes every calculator show an unrealistically long runway.

• Ignoring taxes on traditional account withdrawals, then being surprised when after-tax income falls short.

• Using one average return instead of testing a lower scenario, which hides sequence of returns risk.

• Treating the output as a guarantee rather than an estimate built on assumptions that will not hold exactly.

• Forgetting required minimum distributions, which force withdrawals from traditional accounts starting at age 73 in the United States.

How the Calculation Changes Outside the United States

Canadian retirees typically model an RRSP or RRIF, which carries mandatory minimum withdrawal percentages that rise with age. United Kingdom pension drawdown must account for the personal allowance and income tax bands that apply once money leaves a pension pot. Australian superannuation carries compulsory minimum drawdown rates similar to Canada. Indian calculators typically blend the Employee Provident Fund, the National Pension System, and personal investments, each taxed differently. In Pakistan, where formal pension coverage is limited, most people planning around this question are estimating how long personal savings, gold, or property income will support them, so the same formula becomes a manual spreadsheet rather than a bank-provided tool.

Conclusion

A how long will my money last calculator gives you a number, but the value comes from understanding what drives it: your withdrawal rate, your realistic rate of return, inflation, taxes, and the order in which market returns arrive. Whether you use Fidelity, Bankrate, NerdWallet, CalcXML, or Mutual of Omaha, the formula never changes, only the inputs each tool lets you control. Run your numbers more than once, test a lower return scenario, account for taxes honestly, and revisit the calculation every year rather than treating one result as final.

Frequently Asked Questions

Q: How long will $750,000 last in retirement at 62?

At a 4 percent withdrawal rate, $750,000 typically lasts about 30 years, covering a 62-year-old through the early 90s, though the exact number shifts with your return and Social Security timing.

Q: Will my money double in 7 years?

Use the Rule of 72, dividing 72 by your expected annual return. A 7 percent return doubles money in about 10.3 years, so doubling in 7 years requires a return closer to 10 percent. You can test your own numbers with a compound interest calculator.

Q: Is $2 million enough to retire at 40?

Often yes, provided the withdrawal rate stays near 3 to 3.5 percent rather than the standard 4 percent, since a retirement starting at 40 needs to fund 50 or more years.

Q: What is the 70/20/10 rule for money?

It is a budgeting framework where 70 percent of income covers living expenses, 20 percent goes toward saving or investing, and 10 percent goes toward debt repayment or giving.

Q: What percentage of Americans retire with $1,000,000?

Fewer than 5 percent of Americans hold $1 million or more in retirement accounts, according to Federal Reserve Survey of Consumer Finances data, and the typical retiree aged 65 to 74 holds closer to $200,000.

Q: Can I retire at 40 with 7 million dollars?

Yes, comfortably for most spending levels. Even a conservative 3 percent withdrawal rate provides $210,000 in year one, well above typical household spending.

Q: Can I retire at 45 with $1 million?

It depends on spending. A 3.5 percent withdrawal rate provides about $35,000 in year one before other income, workable for a modest lifestyle or one supplemented by part-time work.

Q: Can I retire at 51 with 2 million dollars?

In most cases, yes, using a withdrawal rate near 3.5 percent for a 40-plus-year horizon, providing about $70,000 in year one before tax.

Q: What age can I retire?

There is no single legal retirement age. Full Social Security benefits begin between 66 and 67 depending on birth year, with reduced benefits from 62, but the more useful marker is when your calculated withdrawal rate supports your desired spending.

Q: Can I live off interest on 2 million dollars?

At a 4 percent yield, $2 million generates about $80,000 per year without touching principal, which for many households is a sustainable income stream, depending on prevailing interest rates.