Retirement Income Calculator

By:
Patrick Myers
Patrick Myers Patrick Myers is the CEO and Founder of Calculator Academy. He has over eight years of experience developing online calculators and holds a B.S. in Mechanical Engineering. His work focuses on formula implementation, calculator accuracy, unit conversions, and creating practical tools that are easy to use.
Last Updated: October 22, 2026

Estimate net monthly retirement income from investments, Social Security, and pensions or calculate the portfolio needed for a target income after tax.

4% is the common rule of thumb. It is a cash-flow assumption, not an investment return or a guarantee that savings will last.

Your total income tax divided by taxable income (federal plus state). Enter 0 to see income before tax.

Share of benefits counted as taxable income, not a tax rate. 85% is the maximum; lower incomes may have less taxed.

Pension, other income and taxable share

100% for traditional IRA or 401(k) withdrawals; 0% for Roth; in between for a mix or taxable accounts.

Retirement Income Formula

Retirement income combines portfolio withdrawals with Social Security, pensions, and other income, then subtracts estimated tax.

Estimated annual net income is:

Net\ Income=Gross\ Income-Taxable\ Income*Effective\ Tax\ Rate

To solve for the portfolio:

Portfolio=max(0,AnnualTarget-FixedAnnualNet)/[WithdrawalRate*(1-TaxableShare*TaxRate)]
A positive gap requires a positive after-tax withdrawal rate.
Required portfolio rounds up to a whole USD cent.

Variables:

  • gross income includes all entered sources
  • taxable income uses the selected taxable shares
  • the effective tax rate applies to modeled taxable income
  • the withdrawal rate determines portfolio cash flow

Income mode estimates net monthly income from a known portfolio. Portfolio-needed mode starts from a target and fills the gap after fixed income.

Taxable-share inputs describe the portion of cash withdrawals recognized as taxable income, which need not equal the proportion held in an account type. Enter only the taxable pension portion in the taxable-pension field and include any tax-free portion with tax-free income, without double counting.

A withdrawal rate is a planning assumption, not a guarantee of sustainability.

Monthly Income Source Example

Illustrative gross cash flow before the simplified tax estimate.

SourceMonthlyAnnual
Social Security$2,500$30,000
Pension$1,500$18,000
Other taxable income$500$6,000
4% from $1,000,000$3,333$40,000
Total gross$7,833$94,000

Example Problems

Example 1: Estimate net income.

A $1 million portfolio at 4 percent adds $40,000 annually to $54,000 of fixed income before the tax estimate.

Example 2: Solve for a portfolio.

Enter a $7,000 net monthly target and the calculator divides the remaining after-tax gap by the after-tax withdrawal rate.

Frequently Asked Questions

Should Social Security be entered before tax?

Enter the gross benefit and its estimated federal-taxable share, from zero to 85 percent for ordinary U.S. Social Security benefits. This share is not a tax rate. The calculator does not determine the income-dependent IRS taxable amount.

How do I estimate portfolio taxable share?

Estimate the share of cash withdrawals that is taxable after considering account basis and distribution rules. The simplified fixed-share model does not calculate deductions, tax brackets, state taxes or how Social Security taxability may change with withdrawals.

Does this model inflation?

It is a one-year income snapshot; use consistent current or future dollars for every input.

Retirement Income Calculator screenshot