What is a gross-up calculation?
A gross-up starts with the net amount you want someone to receive and solves backward for a gross payment after specified withholding and payroll taxes.
Why does this calculator ask for withholding rates?
Many gross-up scenarios use flat assumptions, especially for certain supplemental payments. Regular payroll withholding can be more complex, so the calculator requires the rates you want it to use instead of silently assuming a universal payroll rate.
Why does year-to-date wage information matter when FICA is included?
Social Security tax applies only up to the annual wage base and Additional Medicare withholding begins after an employer pays more than $200,000 of Medicare wages in the year. The year-to-date wage input lets the solver account for those thresholds.
Is a gross-up always deductible to the employer or tax-free to the employee?
No. Gross-up treatment depends on the payment and applicable tax law. This calculator only solves the arithmetic of the specified withholding assumptions.
Frequently asked questions
Sources and methodology
The calculator uses the current federal figures or official agency guidance described below where those rules apply. State-specific results should always be checked with the relevant state tax authority.