Retirement Withdrawal Calculator

Turning a retirement balance into monthly income is different from building the balance. During accumulation, volatility can be uncomfortable but contributions may continue. During retirement, withdrawals leave the account while markets move, and inflation can quietly make a flat payment less useful each year. This retirement withdrawal calculator estimates the first monthly payment that a projected balance can support when payments rise with inflation for a chosen number of retirement years.

The result is a drawdown calculation, not a promise. It is best used to compare scenarios: retiring earlier or later, taking payments at the beginning or end of the month, changing the retirement return, or planning for a longer retirement. Use the compound interest calculator to study accumulation, the retirement age calculator to test readiness age, and the RMD calculator to understand later mandatory withdrawals from many tax-deferred accounts.

Sustainable drawdown and the 4 percent rule

Many retirement conversations begin with the 4 percent rule: withdraw roughly 4 percent in the first year, adjust later withdrawals for inflation, and monitor the portfolio. This calculator is not locked to that rule. It solves an account-specific annuity problem from your balance, planned retirement age, number of retirement years, return during retirement, inflation during retirement, and payment timing. The answer may be above or below a simple 4 percent starting draw, depending on the assumptions.

The calculator first projects the current balance to the retirement age:

$\text{balance at retirement} = \text{current balance} \times (1 + \text{return before retirement})^{\text{years to retirement}}$

It converts annual return during retirement and annual inflation during retirement into monthly rates. Then it prices a growing monthly payment over all retirement months:

$\text{base factor} = \frac{1 - \left(\frac{1 + \text{monthly inflation}}{1 + \text{monthly return}}\right)^{\text{months}}}{\text{monthly return} - \text{monthly inflation}}$

For end-of-month withdrawals, the annuity factor is the base factor. For beginning-of-month withdrawals, the factor is:

$\text{annuity factor} = \text{base factor} \times (1 + \text{monthly return})$

Finally, the starting monthly payment is:

$\text{first monthly withdrawal} = \frac{\text{balance at retirement}}{\text{annuity factor}}$

When monthly return and monthly inflation are nearly equal, the calculation uses a special equal-rate factor to avoid unstable division.

Worked example

Use the defaults: current retirement balance $250,000, current age 45, planned retirement age 65, planned retirement length 30 years, annual return before retirement 6 percent, annual return during retirement 5 percent, inflation before retirement 2 percent, inflation during retirement 2 percent, and withdrawals at the beginning of each month.

There are 20 years until retirement. The current balance grows at 6 percent for 20 years:

$250000 \times (1 + 0.06)^{20} = 801783.8681$

So the projected balance at retirement is $801,783.87. The calculator converts 5 percent and 2 percent annual assumptions into monthly return and inflation rates, then prices 360 monthly withdrawals. Because withdrawals are at the beginning of each month, the factor is adjusted for timing. The first monthly withdrawal is $3,330.18. The first annual withdrawal is $39,962.16, and the today’s-dollar monthly equivalent is $2,241.12 after discounting the first payment by 20 years of 2 percent pre-retirement inflation.

That starting withdrawal is close to, but not exactly, a 4 percent rule amount. Four percent of $801,783.87 is about $32,071.35 for the first year. The calculator allows a larger first year in this scenario because it assumes a fixed 30-year horizon, 5 percent annual return during retirement, and a planned spend-down rather than preserving principal indefinitely.

What the calculator does not decide

The model does not choose which account to tap first. A taxable brokerage account, traditional IRA, Roth IRA, 401(k), 403(b), pension payment, and Social Security benefit each has different tax treatment and flexibility. The calculator also does not reserve money for emergencies, long-term care, home repairs, or bequests. If you want a legacy balance, enter fewer retirement years only with care; the more direct approach is to lower the withdrawal result or keep a separate reserve outside the modeled spending account.

Practical tips for withdrawals

• Test longer life spans than you expect; running out late in retirement is harder to fix.
• Compare beginning-of-month and end-of-month timing if the account is tight.
• Keep taxes separate. A traditional IRA withdrawal and a Roth withdrawal can have very different spendable results.
• Do not ignore required minimum distributions, which can force larger taxable withdrawals later.
• Re-run the numbers after major market moves instead of relying on a stale first-year amount.
• Pair this tool with the savings goal calculator if the projected balance is too low.

This calculator is informational and is not financial, tax, or investment advice. Withdrawal rules, IRS limits, RMD ages, plan features, taxes, and market conditions change. Consider current official guidance and professional advice before making irreversible retirement-income decisions.

Sources

• IRS, Retirement topics: required minimum distributions — RMD rules that can affect retirement withdrawals.
• IRS, Publication 590-B — IRA distribution guidance.
• U.S. Department of Labor, Retirement plans — federal retirement plan information.
• IRS, Retirement plans — federal tax information for retirement plans.

Formula references

• Claim: grow current balance to retirement, then solve annuity withdrawal; beginning timing multiplies ordinary-annuity factor by (1+r). Source: Compound Interest Calculator, U.S. Securities and Exchange Commission, Investor.gov. Version: live federal investor tool accessed 2026-07-09. Jurisdiction: United States; arithmetic is general. Accessed 2026-07-09.
• Claim: grow current balance to retirement, then solve annuity withdrawal; beginning timing multiplies ordinary-annuity factor by (1+r). Source: Principles of Finance, OpenStax, Rice University (peer-reviewed open textbook). Version: 2022 first edition, ISBN 978-1-951693-54-1. Jurisdiction: Jurisdiction-neutral finance definitions. Accessed 2026-07-09.

These sources support only the claims described above. This calculator is informational and does not replace qualified domain, legal, consumer-credit, payroll, mortgage, pensions, or retirement advice.