401(k) Contribution Optimizer
Use the 401(k) Contribution Optimizer
See how increasing pre-tax retirement contributions changes take-home pay and tax drag in the United States.
- Tax-sheltering visibility
- Take-home pay impact
- Contribution scenario comparison
Enter the current pay-period contribution, target rate, filing details, pre-tax benefits, employer plan terms, and year-to-date taxable wages before comparing contribution steps.
What this calculator covers
Inputs you can model
- Gross pay per period
- Pay cycle
- Filing status
- State
- Current 401(k) contribution %
- Target 401(k) contribution %
- Contribution step %
- Pre-tax medical per period
- State allowance count
- State personal exemptions
Results you can review
- Target net take-home
- Net pay reduction
- Annual retirement contribution
- Estimated annual tax savings
- Contribution scenarios
Method, policy basis, and limitations
How the estimate is built
Each scenario applies eligible pre-tax 401(k) deferrals to income-tax withholding while preserving applicable FICA treatment and annual wage-base logic for the selected payroll profile.
Important limitation
This is a payroll and retirement contribution estimate, not tax or plan advice. Plan eligibility, annual limits, employer matching, Roth treatment, payroll timing, and individual tax circumstances may differ.
Your inputs
Enter the values you know. Required fields should be completed first, and optional fields can be left blank if they do not apply to your situation.
Run the calculator to see the planning signal, key measures, reconciliation detail, and any schedules or stress scenarios returned for these inputs.
Your results
The top cards show the most important answers first. Detailed schedules, scenario tables, and supporting notes appear underneath for deeper review.
Inputs changed. Run the calculator again to refresh these results; copy, print, PDF, and Excel actions are unavailable until then.
This is a payroll and retirement contribution estimate, not tax or plan advice. Plan eligibility, annual limits, employer matching, Roth treatment, payroll timing, and individual tax circumstances may differ.