How it is calculated
The calculator works out your tax for the whole year and divides it by the number of paychecks. A traditional 401(k) reduces only federal and state taxable wages; Section 125 pre-tax deductions (such as employer health premiums) also reduce Social Security and Medicare (FICA) wages.
Federal taxable wages = salary − 401(k) − pre-tax deductions Taxable income = federal taxable wages − standard deduction Federal income tax = max(0, tax from the brackets − Child Tax Credit) Social Security = min(salary − pre-tax deductions, $184,500) × 6.2% Medicare = (salary − pre-tax deductions) × 1.45% + amount over $200,000 × 0.9% State + local tax = federal taxable wages × the rate you enter Take-home per paycheck = (salary − taxes − 401(k) − pre-tax deductions) ÷ number of paychecks
- Paychecks per year: weekly 52, biweekly 26, semimonthly 24, monthly 12
- Child Tax Credit: $2,200 per child under 17 at the end of the year comes off your tax. It falls by $50 for every $1,000 (or part of $1,000) of modified AGI above $200,000 ($400,000 married filing jointly).
- Refundable portion: Once your tax reaches zero, up to $1,700 per child of the remaining credit, limited to 15% of earned income above $2,500, may be refunded when you file. It doesn’t arrive in your paychecks, so it is shown separately and left out of take-home pay.
2026 federal tax brackets and standard deduction
FICA is Social Security at 6.2% (on up to $184,500 of wages in 2026) plus Medicare at 1.45% with no cap; wages above $200,000 also owe an additional 0.9% Medicare tax. The 401(k) employee contribution limit is $24,500.
| Rate | Single (taxable income) | Married filing jointly | Head of household |
|---|---|---|---|
| 10% | $12,400 or less | $24,800 or less | $17,700 or less |
| 12% | $50,400 or less | $100,800 or less | $67,450 or less |
| 22% | $105,700 or less | $211,400 or less | $105,700 or less |
| 24% | $201,775 or less | $403,550 or less | $201,750 or less |
| 32% | $256,225 or less | $512,450 or less | $256,200 or less |
| 35% | $640,600 or less | $768,700 or less | $640,600 or less |
| 37% | Over $640,600 | Over $768,700 | Over $640,600 |
| Standard deduction | $16,100 | $32,200 | $24,150 |
IRS Rev. Proc. 2025-32 (reflecting the 2025 tax law changes). Taxable income is after the standard deduction.
Example: single, $85,000 salary
Paid biweekly, 6% to a 401(k), $2,400 a year of pre-tax deductions such as health premiums, no children and a 5% state income tax.
Federal taxable wages are $85,000 − $5,100 − $2,400 = $77,500, and taxable income after the $16,100 standard deduction is $61,400. Federal income tax is $5,800 + ($61,400 − $50,400) × 22% = $8,220 — an effective rate of about 9.7% and a 22% marginal rate.
FICA applies to $82,600, because the 401(k) contribution isn’t subtracted. With the calculator’s default 0% state tax, the paycheck is $2,421.58.
| Item | Per year | Per paycheck (26) |
|---|---|---|
| Salary | $85,000 | $3,269.23 |
| 401(k) 6% | −$5,100 | −$196.15 |
| Pre-tax deductions | −$2,400 | −$92.31 |
| Federal income tax | −$8,220 | −$316.15 |
| Social Security | −$5,121.20 | −$196.97 |
| Medicare | −$1,197.70 | −$46.07 |
| State tax 5% | −$3,875 | −$149.04 |
| Take-home pay | $59,086.10 | $2,272.54 |
What isn’t included
- Employers withhold from each paycheck using your W-4 and the IRS Pub 15-T tables, so actual withholding can differ from this estimate by a few dollars. Your final tax is settled on next year’s Form 1040.
- State brackets and deductions vary, so state tax is approximated with the single rate you enter. Some states, such as Pennsylvania, tax 401(k) contributions, and some cities, such as New York City and Philadelphia, add their own income tax.
- The tips and overtime deductions and the extra deduction for people 65 and older created by the 2025 tax law (the One Big Beautiful Bill Act), itemized deductions and other income (interest, dividends, side gigs) are not included.
- 401(k) catch-up contributions for people 50 and older and Roth 401(k) contributions are not modeled. Roth contributions are after-tax, so they don’t reduce taxable wages.
- Employers withhold the Additional Medicare Tax above $200,000, but the actual threshold for joint filers is $250,000, so the difference is settled when you file. State-mandated employee contributions such as California SDI are not included.
FAQ
What’s the difference between biweekly and semimonthly?
Biweekly means every two weeks, 26 paychecks a year; semimonthly usually means the 15th and the last day of the month, 24 a year. For the same salary, each biweekly check is smaller, and twice a year you get three paychecks in one month.
Does a 401(k) contribution cut my take-home pay by the full amount?
No. A traditional 401(k) lowers your federal (and in most states, state) taxable wages, so your tax falls too. In the example, contributing $5,100 saves tax at 22% federal plus 5% state, so take-home pay drops by only about $3,723. Social Security and Medicare are still owed on it.
How does the Child Tax Credit show up in my paycheck?
If you list your children in Step 3 of your W-4, your employer withholds less, spreading the credit across your paychecks. This calculator subtracts it from tax the same way. Any refundable amount beyond your tax comes when you file.
Which states have no income tax on wages?
In 2026, Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington and Wyoming don’t tax wages. Washington taxes only certain capital gains, although a law passed in 2026 is set to add a 9.9% tax on income above $1,000,000 starting in 2028. Enter 0 for these states.