Why use this calculator
The number on your offer letter is not the number you can spend. Between the federal brackets, Social Security, Medicare, a state rate that swings from zero to double digits, health premiums and a retirement deferral, a third of gross pay can disappear before the deposit hits.
This calculator rebuilds the stack in the order payroll actually applies it, so you can see which deduction is doing the damage and test a change before you make it. It is built for the United States and uses the tax year 2026 federal figures published by the IRS.
Most importantly it separates the effective rate, which is what you really pay across all your income, from the marginal rate, which is what the next raise or bonus dollar is charged. Confusing the two is why people turn down overtime believing it will push them into a bracket that costs them money, which is not how a progressive system works.
How to use it
- Enter the gross amount for a single pay period, taken from the very top line of your pay stub before any deduction, not your annual salary.
- Pick the pay frequency printed in the pay period header, because bi-weekly and semi-monthly look similar and produce different annual totals.
- Choose the filing status you ticked in Step 1(c) of your Form W-4, since it sets both the standard deduction and the bracket widths.
- Put health, dental, vision, FSA and payroll HSA amounts into pre-tax benefits, copying the figures from the pre-tax deductions block of the stub.
- Enter your traditional 401(k) deferral as a percentage of gross, which your retirement portal shows as the deferral rate.
- Finally enter your state income tax rate, or zero if you work in a state that does not levy one.
What each result means
- Gross pay this period
- Your pay before any deduction, the figure your salary or hourly rate produces for one pay period.
- Pre-tax benefits
- Section 125 amounts removed before both income tax and payroll tax, which makes them the cheapest dollars on the stub.
- 401(k) contribution
- The traditional deferral leaving this paycheck. It reduces federal and state tax immediately but still pays Social Security and Medicare.
- Federal income tax
- Estimated federal withholding for this period, based on annualised wages, the standard deduction and the 2026 brackets.
- Social Security
- The 6.2% old-age and survivors tax, which stops for the year once your wages pass the contribution and benefit base.
- Medicare
- The 1.45% hospital insurance tax on every dollar of wages, with an extra 0.9% on high earners and no upper limit.
- State income tax
- Your state rate applied to the same wage base as federal tax. Nine states charge nothing on wage income.
- Net pay (take-home)
- The amount deposited in your account for this pay period, and the only figure your budget should ever be built on.
- Each extra 1% to your 401(k) costs
- How much smaller each paycheck would be if you raised your 401(k) deferral by one percentage point. It is less than the amount deferred because that money is not subject to federal or state income tax now.
- Take-home share of gross
- The percentage of gross pay you actually keep. Watching this move is the fastest way to judge any payroll change.
- Effective tax rate on gross
- All tax withheld divided by gross pay. It is always lower than your bracket, because early income is taxed at lower rates.
- Marginal federal rate
- The federal rate charged on your next taxable dollar. Overtime, a bonus or a raise is taxed at this rate, not your whole income.
- Annualised gross pay
- Gross pay multiplied by the number of pay periods in the year, which is the base for bracket and wage-cap tests.
- Annualised take-home pay
- Your projected net pay for a full year at this rate, useful for checking a rent or mortgage application.
The formula
Take-home = Gross minus pre-tax benefits, minus the 401(k) deferral, minus federal income tax, minus FICA, minus state tax
FICA wages are gross less Section 125 pre-tax benefits only, because a traditional 401(k) deferral escapes income tax but not payroll tax. Federal taxable income is FICA wages less the deferral less the 2026 standard deduction (single $16,100, married filing jointly $32,200, head of household $24,150), then run through the 2026 marginal brackets. Social Security is 6.2% of wages up to the $184,500 contribution and benefit base; Medicare is 1.45% of all wages with no ceiling, plus 0.9% above $200,000 single or $250,000 joint.
How this number is used in practice
The most common use of a paycheck estimate is not curiosity, it is a decision. You are weighing a job offer in a different state, deciding whether to take the extra shift, or working out whether you can afford to raise your deferral from 4% to 8%.
Because a traditional deferral comes out before income tax, raising it costs less take-home than the headline number suggests: a worker in the 22% federal bracket with a 5% state rate gives up roughly 73 cents of take-home for every extra dollar saved. Running the change here before you submit the payroll form tells you whether the new net pay still clears your rent.
The second use is fixing withholding. A large refund feels like a windfall, but it is an interest-free loan you made to the federal government for up to sixteen months. On a $3,600 refund that is about $300 a month you could have been paying down a card at 22% or holding in a savings account.
The fix is Form W-4: Step 4(c) adds extra withholding if you are short, and Step 4(b) claims deductions if you are consistently over. Run your paycheck here, compare the federal line against the withholding on your last stub, and adjust once rather than living with the gap all year. Aim to owe or be owed a few hundred dollars, not a few thousand.
Watch the Social Security line if you earn above the wage base. Once your year-to-date wages pass the contribution and benefit base, the 6.2% stops and your remaining paychecks jump by that amount until January resets it. Payroll departments rarely warn people, so a December paycheck that is several hundred dollars larger is not an error and should not be treated as permanent income.
Worked examples
$5,000 bi-weekly, single, 6% to a 401(k), $200 pre-tax benefits, 5% state tax
Net pay of $3,257.42 a paycheck, an effective tax rate of 24.85% on gross and a 22% federal marginal rate.
$4,000 semi-monthly, married filing jointly, no deferral, no state income tax
Net pay of $3,395.67 a paycheck, an effective rate of just 15.11%, because the joint standard deduction and wider brackets cut federal tax sharply.
$2,000 weekly, head of household, 25% deferral, $150 pre-tax benefits, 4.5% state tax
Net pay of $1,072.35 a week, with the deferral held at $471.15 because 25% of salary would breach the $24,500 annual limit.
When people use it
- Budgeting rent, loan repayments and childcare from real net pay instead of gross salary
- Testing what raising or cutting your 401(k) deferral does to the deposit you actually receive
- Comparing two job offers in states with very different income tax rates
- Checking whether your current withholding is heading for a large refund or a surprise bill
- Working out the after-tax value of an overtime shift or a bonus at your marginal rate
Tips
- Budget on net pay, never gross. Lenders and landlords quote gross, and the gap is often a third of the number.
- Your effective rate is far lower than your bracket. A 22% bracket usually means an effective federal rate in the low teens.
- A big refund is an interest-free loan to the government. Adjust Form W-4 Step 4 so you land within a few hundred dollars either way.
- Pre-tax health premiums dodge income tax and payroll tax; a 401(k) deferral dodges income tax only. That makes benefit dollars cheaper than deferral dollars.
- If you are paid bi-weekly you get 26 paychecks, so two months a year contain three. Budget on 24 and treat the extra two as a bonus.
- Contribute at least enough to capture the full employer match before you optimise anything else on this page.
- Check the Social Security line each December. If it has stopped, your wages passed the annual cap and the rise is temporary.
What it assumes, and where it stops being accurate
- Federal tax uses the 2026 standard deduction and marginal brackets. It does not model itemised deductions, the child tax credit, the earned income credit or any other credit.
- State tax is applied as a single flat rate to the federal wage base. Real state systems have their own brackets, deductions and exemptions.
- City, county and school district income taxes are excluded, which understates withholding in places such as New York City, Philadelphia and much of Ohio.
- Your income is assumed to be wages taxed under this one job. A second job, self-employment income, investment income or a working spouse changes the result.
- Post-tax deductions such as Roth 401(k) contributions, union dues, garnishments and after-tax insurance are not modelled.
- Employer payroll systems use the IRS percentage method tables from Publication 15-T, so your stub can differ from this estimate by a few dollars a period.
Terms used on this page
- FICA
- The Federal Insurance Contributions Act payroll taxes: 6.2% Social Security up to the wage base plus 1.45% Medicare on everything.
- Contribution and benefit base
- The annual wage ceiling above which Social Security tax stops being charged. It is $184,500 for 2026.
- Section 125 plan
- A cafeteria plan letting employees pay health and similar premiums before both income tax and payroll tax are calculated.
- Marginal rate
- The tax rate applied to your next dollar of taxable income, as opposed to the average rate across all of it.
- Form W-4
- The employee withholding certificate that tells payroll how much federal tax to take from each paycheck.
Questions people ask
- Why does my actual pay stub differ from this estimate?
- Employers withhold using the percentage method tables in IRS Publication 15-T, which annualise your pay slightly differently and respond to every entry on your Form W-4, including dependent credits and other income. This calculator uses the published brackets directly. Differences of a few dollars per period are normal; differences of hundreds usually mean a credit, a second job or a local tax is involved.
- Does a 401(k) contribution really lower my tax straight away?
- A traditional deferral does. It is removed from your wages before federal and state income tax are calculated, so a worker in the 22% bracket with a 5% state rate keeps about 27 cents of every deferred dollar in tax saved. It does not reduce Social Security or Medicare, which are charged on the full wage. A Roth 401(k) deferral gives no deduction now and comes out tax-free later.
- What is the difference between my marginal rate and my effective rate?
- The marginal rate is the percentage charged on your next dollar of taxable income, and it decides the value of overtime, a bonus or a deduction. The effective rate is total tax divided by total income, which is always lower because the first slices of income are taxed at 10% and 12%. A raise never reduces your take-home pay, because only the dollars above a threshold are taxed at the higher rate.
- Why did my Social Security deduction stop late in the year?
- Social Security tax applies only to wages up to the annual contribution and benefit base, which is $184,500 for 2026. Once your year-to-date wages pass that ceiling the 6.2% stops for the rest of the calendar year and your paychecks get larger. Medicare has no ceiling and keeps being charged on every dollar, with an extra 0.9% above $200,000 single or $250,000 filing jointly.
- Should I aim for a big tax refund?
- No. A refund means you lent the government money all year at zero interest and only got it back after filing. A $3,600 refund is $300 a month you could have used to clear a credit card charging over 20%, or to hold in a savings account earning interest. Adjust Form W-4 Step 4 so your withholding lands within a few hundred dollars of the true bill either way.
- Does this calculator include local and city income taxes?
- No. It models federal tax, Social Security, Medicare and a single state rate that you supply. Residents of New York City, Philadelphia, Detroit and many Ohio and Pennsylvania municipalities pay an additional local income tax of roughly one to four percent, which this estimate does not deduct. Add it to the state rate field if you want an approximation of the combined burden.
Use this with
Paycheck Calculator answers one part of the question. These pick up where it stops: Salary After Tax Calculator, Tax Refund Estimator, Australian Income Tax Calculator, Hourly to Salary Converter and Budget Planner Calculator.
Where these figures come from
Figures and rules on this page follow United States federal rules.
- IRS Rev. Proc. 2025-32: inflation adjustments for tax year 2026. Federal marginal brackets and standard deduction used by this calculator
- Social Security Administration: Contribution and Benefit Base. The annual wage ceiling above which Social Security tax stops
- Internal Revenue Service. Federal income tax rules and forms for tax year 2026
Paycheck Calculator produces an estimate for general information. It is not financial, tax, medical, legal or engineering advice. read the full disclaimer. Spotted a wrong number? Report it and it gets fixed. The form picks up this calculator and the inputs you used.