401(k) Calculator

Enter your current age, intended retirement age, and the age through which you want to project withdrawals. “Life Expectancy” is a planning endpoint you choose; the tool does not calculate your life expectancy. Add your current 401(k) balance, annual salary, and the percentage of salary you contribute. The model adds employee and employer contributions once per working year and applies growth and fees to the starting balance for that year. New contributions start earning the entered return the following modeled year.

The employer match has two inputs. If “Employer Match Rate” is 50% and “Match Applies Up To” is 6% of salary, the model contributes 50 cents for each dollar of your contribution up to 6% of salary. At the default $75,000 salary and 10% employee contribution, that means $7,500 from you and $2,250 from the employer in the first modeled year. Your plan may use a different formula, eligibility rule, or matching schedule; check its summary plan description. For a closer look at contributions, use the 401(k) contribution calculator.

“Annual Withdrawal in Retirement” is a target amount at the retirement age you enter. The calculator raises that target by your inflation assumption in later years and caps each withdrawal at the available balance. It does not calculate a sustainable withdrawal amount for you. Compare this target with your spending gap after Social Security and pensions using the retirement income calculator.

While you are working, the calculator grows salary by the advanced salary-growth rate and, if enabled, adds the escalation rate to your contribution percentage points each year until the escalation cap. It limits your employee contribution by the built-in age-based dollar cap. Employer matching is based on the smaller of your actual employee contribution or the salary percentage eligible for matching.

Employee contribution = min(salary × contribution %, modeled employee limit)
Employer match = min(employee contribution, salary × match limit %) × match rate
Working-year ending balance = starting balance × (1 + return − fee rate)
                            + employee contribution + employer match

Planned retirement withdrawal = entered annual withdrawal × (1 + inflation) ^ years retired
Actual retirement withdrawal = min(starting balance, planned withdrawal)
Retired-year ending balance = (starting balance − actual withdrawal) × (1 + return − fee rate)

Returns and fees are entered as percentages; the formulas above use decimal rates. The model applies a constant nominal return and fee percentage, with no market losses, variation, or midyear deposits. The balance-at-retirement card now shows the amount before the first retirement withdrawal. In the year-by-year table, the row at retirement age shows the balance after that year's withdrawal and growth. That timing explains why the two figures differ.

The “Your Contributions” card totals employee deposits during working years. “Employer Match” is the modeled career match multiplied by an estimated vesting fraction at retirement; the balance projection itself does not remove unvested employer dollars. “Investment Growth” and “Fees Paid” accumulate over the entire projection, including retirement years, so they are not a breakdown of the balance at retirement. The “lasts until” age is the first modeled age at which the balance reaches zero, or your chosen endpoint if it stays positive. No year beyond that endpoint is projected.

The calculator now uses these 2026 dollar limits for a standard 401(k):

It also uses a $72,000 annual additions cap for regular employee and employer contributions, excluding catch-up contributions. These match the IRS 2026 limits for standard plans. The model reuses the 2026 dollar limits in every future projected year; it does not forecast inflation adjustments or future law changes. Actual permitted contributions can also be lower because of compensation, plan terms, other retirement plans, and tax rules. The 401(k) max contribution calculator is useful for a separate annual limit check.

In advanced settings, the current tax-rate input produces a rough current tax-reduction estimate: projected Traditional employee contributions multiplied by your entered rate. If you enable the Roth option, the selected Roth percentage reduces the portion treated as Traditional for this estimate. The tool does not calculate tax brackets year by year, future tax on Traditional withdrawals, or a true after-tax Traditional-versus-Roth comparison. The “Expected Retirement Tax Rate” input does not change the main projection. For a separate comparison, use the Roth 401(k) calculator; for withdrawal taxes, use the 401(k) withdrawal tax calculator. Traditional distributions are generally taxable, while qualified designated Roth distributions can be tax-free. IRS: Tax on normal distributions

The vesting inputs estimate how much of the cumulative employer match you would own by retirement if you remain with the same employer. Vesting does not reduce the projected account balance or alter annual growth in this model. Your real plan's vesting schedule may be graded or cliff-based, so check your plan statement before treating the displayed match as yours to keep.

The strongest test is to rerun the calculator with lower returns, higher fees, higher inflation, and a later planning endpoint. A steady 7% return can hide the effect of a loss early in retirement. The tool does not model market volatility, required minimum distributions, taxes on withdrawals, changes in employer match, or extra withdrawals for unexpected expenses. Its prominent result is a scenario, not a verdict on whether you can retire.

If the balance runs out too early, test a contribution increase, a later retirement age, or a smaller withdrawal target. The 401(k) future value calculator can isolate the savings phase; the retirement withdrawal calculator can explore the spending phase in more detail.