Gross Up Paycheck Calculator
When an employer promises a $5,000 bonus “after taxes,” the check that arrives is never $5,000. Federal withholding, Social Security, Medicare, and state taxes all take their slice first, so payroll has to work backward: start from the net amount the employee should receive and gross it up to the paycheck figure that produces it.
The Gross Up Paycheck Calculator below does that backward math. Enter the net pay you want the employee to take home, set the tax components (with one-click presets for the common bonus case: 22% federal supplemental withholding plus 7.65% FICA), and get the gross pay required with a full tax breakdown.
Enter the desired take-home pay and tax rates to find the gross pay required.
Gross pay required
Withholding is an estimate, not final tax liability. The 22% federal supplemental rate (37% above $1M) comes from IRS Publication 15. FICA is 6.2% Social Security plus 1.45% Medicare.
How to use the Gross Up Paycheck Calculator
Enter the take-home amount in the net pay box. Use a preset for the common cases (bonus with federal plus FICA, FICA only, or no tax), or type your own federal, FICA, and state percentages. Press Calculate to get the gross pay required, with every tax slice itemized and a net-check line proving the arithmetic closes.
Formula
The gross-up formula is gross pay = net pay / (1 – combined tax rate). Each component is a flat percentage of the gross: federal withholding = gross x federal %, FICA = gross x 7.65% (6.2% Social Security + 1.45% Medicare), state = gross x state %. The combined rate is the sum of the three, and the result always satisfies gross – total tax = net pay.
Worked example
An employer wants a $200 net bonus with only FICA withheld (7.65%). Gross = 200 / (1 – 0.0765) = 200 / 0.9235 = $216.57. The FICA slice is 216.57 x 7.65% = $16.57, and 216.57 – 16.57 = $200.00 net, exactly as required. For a $5,000 net bonus with 22% federal plus 7.65% FICA (29.65% combined): gross = 5,000 / 0.7035 = $7,107.32, with $1,563.61 federal and $543.71 FICA withheld.
Percentage method vs aggregate method
For bonuses paid on a separate check, employers use the percentage method: a flat 22% federal withholding (37% on amounts above $1 million in a year), per IRS Publication 15. When the bonus lands on the same check as regular pay, the aggregate method applies instead: withholding follows the employee’s W-4 as if the bonus were ordinary wages. Either way, Social Security and Medicare apply on top. Note that withholding is not your actual tax: if your marginal rate is lower you get the difference back at filing time.
Common gross-up scenarios
Bonuses are the classic case, but the same math covers severance packages quoted as net amounts, relocation payments an employer wants to make whole, and freelance negotiations where you need a gross rate that leaves your target take-home after self-employment tax. In each case the question is identical: what gross figure, after the known deductions, leaves exactly this net?
What competitors miss
Payroll guides publish the formula but make you do the arithmetic by hand, and their worked examples stop at FICA-only cases. Generic net-to-gross tools use one flat rate with no breakdown, so you cannot see how much goes to federal vs FICA vs state. This tool combines the payroll-correct component model with a self-verifying result: the net-check line shows gross minus tax equals your target net, so the math is auditable in one glance.
Frequently asked questions
What does it mean to gross up a paycheck?
It means calculating the gross pay needed so that, after taxes and deductions, the employee receives a specific net amount. Employers do this for bonuses, severance, and relocation payments quoted as take-home figures.
What is the formula for grossing up?
Gross pay = net pay / (1 – tax rate). With a 7.65% FICA-only rate, a $200 net bonus needs $200 / 0.9235 = $216.57 gross.
Are bonuses taxed at a higher rate?
Bonuses are supplemental wages. Employers may withhold federal income tax at a flat 22% (37% above $1 million), but that is withholding, not your final tax rate: the bonus is ultimately taxed at your marginal rate when you file.
Do Social Security and Medicare apply to bonuses?
Yes. FICA taxes (6.2% Social Security + 1.45% Medicare = 7.65%) apply to bonuses and other supplemental wages on top of income tax withholding.
What is the difference between the percentage and aggregate methods?
The percentage method (flat 22%) applies when the bonus is paid separately from regular wages. The aggregate method applies when it is combined with regular pay on one check, and withholding follows the employee’s W-4.
Can I gross up for state taxes too?
Yes. Enter your state withholding percentage in the state box and it joins the combined rate, so the gross covers federal, FICA, and state together.