Check the match formula before comparing balances
This calculator models one ordinary employer-sponsored 401(k), one salary, and a flat matching formula. Match rate means cents per contributed dollar; the salary percentage sets how much of your contribution can be matched. Tiered formulas, payroll-by-payroll limits, true-ups, profit sharing, and contributions to other plans are outside this model.
In a hypothetical $75,000 salary example, a 50% match on contributions up to 6% of salary matches at most $4,500 of employee contributions. Contributing 3% ($2,250) produces a $1,125 match. Contributing 6% ($4,500) produces a $2,250 match. Increasing the contribution to 10% still produces a $2,250 match. This is contribution arithmetic, not an investment return.
2026 limits used by the model
- Regular employee deferral: $24,500.
- Age 50 through 59 or 64 and older: $8,000 additional catch-up, if permitted.
- Age 60 through 63: $11,250 additional catch-up, if permitted.
- Regular employee plus employer additions: the lesser of $72,000 or annual compensation; catch-up is excluded.
- Compensation considered for the matching formula: at most $360,000.
Age means age at the end of each modeled calendar year. The schedule starts in 2026 and stops before the selected stopping age. Thus an age-63 scenario can use $35,750 of employee deferrals, while age 64 returns to $32,500. These dollar limits remain fixed throughout the projection. Future IRS adjustments, plan-specific lower limits, and nondiscrimination testing are not predicted. See the IRS contribution-limit explanation.
Roth catch-up and the tax estimate
For 2026, the Roth catch-up requirement generally applies when 2025 Social Security wages from the sponsoring employer exceeded $150,000. The IRS 2026 adjustment notice specifies this threshold. The Roth catch-up checkbox applies that treatment to every projected year as a scenario. It does not establish your legal eligibility; confirm the applicable wages and implementation with your plan.
Estimated income-tax deferral equals modeled pre-tax employee contributions times the sum of the entered federal and state rates. Roth catch-up is excluded when selected. This estimate ignores brackets, deductions, state differences, payroll taxes, and withdrawal taxes. It is not lifetime tax savings or an after-tax retirement balance. Changing contribution type does not change the projected balance when the same dollar amount is invested.
Roth employee contributions are included in current taxable income. Qualified Roth distributions require the applicable five-year period and a qualifying condition, such as reaching age 59½. See the IRS Roth account explanation. This tool assumes pre-tax employer matching for simplicity; some plans permit designated Roth employer contributions, as described in IRS Publication 6087.
How the balance projection works
Each year starts with the previous ending balance. That balance grows at (1 + r/n)n − 1, where r is the entered nominal annual rate as a decimal and n is the number of compounding periods. Employee contributions and employer matching are then deposited at year-end. Actual payroll deposits occur throughout the year, so this annual approximation can differ materially from a plan statement.
A $25,000 starting balance, 7% nominal rate compounded annually, $7,500 employee contribution, and $2,250 match produce a hypothetical first-year balance of $36,500. At −10%, the same inputs produce $32,250. Neither rate is a forecast. Fees, inflation, withdrawals, and varying annual returns are omitted; the default 3% salary increase is also only an assumption.
Employer matching is assumed fully vested. Your own deferrals are fully vested, but employer contributions may follow a vesting schedule. Compare the plan document with the IRS vesting explanation before treating the entire modeled match as money you would retain after leaving a job. Use the calculator to compare assumptions, not to select investments or decide a contribution amount without considering your budget.
Rules checked October 21, 2026. Calculations run in this browser and do not connect to a retirement account.