W-4 Calculator 2026: the withholding fixer

Withholding is an estimate; the W-4 is the dial

The federal income tax on your paycheck is your employer's estimate of your annual tax, made with IRS Publication 15-T from the W-4 you gave them. The estimate is exact for one case — one job, one income in the household, the standard deduction, no other income — and drifts in every other. On $85,000 paid every two weeks with a clean W-4 the withholding is $379.62 per paycheck, $9,870 a year against a tax of $9,870: within a few dollars, which is what the tables are built to do.

The drift starts when the year does not match the form. Two $60,000 salaries filed jointly, each withheld as if it were the household's only income, come to $5,680 of withholding against a tax of $10,040 — $4,360 short, which is the April bill two-earner couples know. $12,000 of freelance income with no withholding on top of the $85,000 salary leaves $12,510 short. Two children not entered on step 3 leave -$5,470 over-withheld, lent to the government at no interest until the refund. The calculator finds where your year is heading and writes the lines that move it.

The five steps of the W-4, and what each does to the paycheck

Step 1(c), filing status, picks the withholding table: single or married filing separately, married filing jointly, or head of household. The joint table has the $32,200 deduction and wider brackets built in, so choosing it withholds less per paycheck. Step 2, multiple jobs, corrects the table's assumption that this paycheck is the household's only income: check box 2(c) at both jobs when the two incomes are similar, or use the worksheet for the higher-paying job when they are not. With the box checked the tables' thresholds are halved, so each job is withheld as if it earned half the household's income, which is roughly right.

Step 3, dependents, is an annual dollar amount — $2,200 per child under 17 in 2026, $500 per other dependent — that the percentage method subtracts from the tentative annual withholding before dividing by pay periods. Two children lower a biweekly paycheck's withholding by $169.23. Put it on one W-4 only. Step 4(a), other income, adds income nobody withholds on — interest, dividends, freelance work — so that the tables withhold on it; 4(b), deductions, is for itemised deductions above the $16,100 standard amount; 4(c), extra withholding, is a flat dollar amount taken from every paycheck on top. Step 5 is the signature.

The older form, before 2020, used «allowances» worth $4,300 each; employers still honour it for employees who never filed a new one, but its estimate is cruder and it has no place for a second income. Anyone who has not filed a W-4 since 2019 and has a working spouse, children or side income will usually be better served by the new form.

How the fixer computes the lines

It projects the year: your salary plus your spouse's wages and other income, minus pre-tax contributions and either the standard or your itemised deduction, through the 2026 brackets, minus the credits for the children and dependents you enter. That is the tax. It then projects withholding: what has been withheld so far plus your current per-paycheck federal line times the paychecks left. The gap is the refund or bill the year is heading for. To hit the target you pick — zero, a $500 refund, or a $500 bill — it computes what each remaining paycheck must withhold and expresses the difference as the step 4(c) amount, alongside steps 2 and 3 filled from your answers.

Mid-year corrections work because step 4(c) is per paycheck and the remaining paychecks are known: a $1,300 shortfall discovered with ten paychecks to go is $130 extra on each. A shortfall discovered in December cannot be fixed by withholding and becomes a bill, possibly with an underpayment penalty if it is large; the quarterly estimated payment route exists for that.

Two jobs or a working spouse

This is the case that produces most surprise bills. Each employer applies the full standard deduction and starts the brackets from zero, so two incomes are each under-withheld by roughly the tax on the second one's overlap with the first. The fix is step 2: check box 2(c) on both W-4s if the incomes are within a factor of about two of each other, which halves the thresholds and withholds correctly on each; if one income is much larger, use the multiple-jobs worksheet or the estimator and put the extra on step 4(c) of the larger job. Claim the children on one W-4 only, and do not check 2(c) on one form without the other.

On the two $60,000 example the box changes each paycheck's withholding from $109.23 to $193.08 and closes the $4,360 gap almost exactly. The dual income calculator works the household as a whole.

Claiming exempt

Writing «Exempt» under step 4(c) stops federal income tax withholding entirely (not FICA). It is legal only if you had no federal tax liability last year and expect none this year, which at 2026 rates means income below the $16,100 standard deduction for a single filer with no other income, or a larger income fully offset by credits. It expires every year on 15 February and must be renewed with a new W-4. Claiming it wrongly does not reduce the tax; it moves the whole year's tax to April, with a possible penalty. The claiming exempt guide has the tests.

The state form is separate

The W-4 sets federal withholding. Most states with an income tax have their own certificate — California's DE 4, New York's IT-2104, Georgia's G-4, Illinois's IL-W-4 — and many still use allowances even though the federal form abandoned them; a few states (Utah, New Mexico, North Dakota, Colorado by default) use the federal W-4 for the state line, and the 9 no-tax states have none. Leaving the state form blank makes the employer apply the state's default, usually single with no allowances, which over-withholds for most married workers. Every state page names its form.

How the federal withholding is computed

The percentage method of IRS Publication 15-T has four steps. First, the paycheck's taxable wages are multiplied by the number of pay periods to get an annualised figure — $85,000 on this example. Second, that figure is adjusted: the amounts on steps 4(a) and 4(b) of the W-4 are added and subtracted, and if the box in step 2(c) is not checked a fixed $8,600 ($12,900 for joint filers) is subtracted. Third, the adjusted figure is run through the withholding rate table for the filing status, which gives $9,870 for the year for a single filer with no adjustments. Fourth, the step 3 credits are subtracted, the result is divided back into pay periods, and any extra amount from step 4(c) is added.

The tables are the 2026 brackets and the standard deduction rearranged so that the fixed subtraction works out, which is why a person with one job and a clean W-4 is withheld almost exactly their annual tax — $9,870 here, 11.6% of gross, with the last dollar in the 22% bracket. The «Show me the math» diagram under the paycheck calculator walks through the four steps with your own figures.

The three taxes on a paycheck, and why they behave differently

Federal income tax is progressive and starts from zero: the first $16,100 a single filer earns in 2026 is untaxed because that is the standard deduction, and the rate then climbs through seven brackets from 10% to 37%. It is the only line your W-4 changes. FICA is flat from the first dollar — 6.2% for Social Security up to $184,500 of wages and 1.45% for Medicare without limit — and no form changes it. State income tax is whatever your state decided: nothing in 9 states, one flat rate in 13, brackets in the other 29, and 11 states let a city or county add a line of their own.

On the $3,269.23 biweekly example above: $379.62 of federal withholding, $250.09 of FICA and $0.00 of Texas tax. Keeping them on separate lines is the point: a 401(k) contribution moves the first and third but not the second; a raise moves all three at different rates; the Social Security cap moves only the second. A single «taxes» figure hides which lever does what.

Pay frequency changes the number, not the pay

$85,000 a year is $1,634.62 a week, $3,269.23 every two weeks, $3,541.67 twice a month and $7,083.33 a month. Nothing about the tax changes, only the slice you see on payday — but the slice is what people budget from, and biweekly and semi-monthly are the pair that get confused: the biweekly paycheck is about 7.7% smaller, and in return two months a year contain three of them.

Frequency also affects withholding precision, because the IRS percentage method annualises each paycheck on its own. A monthly paycheck with a bonus in it is annualised twelve times over, a weekly one fifty-two times, which is why bonuses are usually withheld separately at a flat rate. Some years have 27 biweekly or 53 weekly paydays; the advanced panel of the paycheck calculator has both, because payroll software does.

A bonus year, a raise year, a new job

A bonus is withheld at a flat 22% regardless of the W-4, which over-withholds for anyone in the 12% bracket and under-withholds above 24%; enter the bonus as other income on the fixer, or simply accept the refund. A mid-year raise is handled automatically, because each paycheck is annualised on its own — the new, higher paychecks are withheld as if they had run all year, which slightly over-withholds. A new job mid-year over-withholds the same way: the new employer annualises the new salary from its first paycheck, while the earlier months were withheld at the old one. Enter the year-to-date figures from the last stub and the fixer accounts for both.

What changed in 2026

The standard deduction is $16,100 single, $32,200 joint and $24,150 head of household; every bracket threshold moved up with inflation; the Social Security wage base is $184,500; the 401(k) elective limit is $24,500. Each is read from the document that sets it — IRS Revenue Procedure 2025-32, the SSA's contribution and benefit base, IRS Notice 2025-67 — and listed with its source under the calculator.

The bigger change is the set of new federal deductions: qualified overtime premium pay up to $12,500 ($25,000 joint), reported tips up to $25,000, and $6,000 more for each person aged 65 or over, all phasing out above $150,000 of income. None of them changes what an employer withholds, because Publication 15-T does not know about them; they reduce the tax owed at filing, which is why the calculators on this site show them in the «withholding vs what you owe» box rather than on the paycheck. The what changed in 2026 guide keeps the dated list, including state changes.

A worked example: $45,000 in New York, paid every two weeks

Take $45,000 a year in New York, paid every two weeks (26 paychecks), single, standard W-4, no pre-tax deductions. The gross per paycheck is $1,730.77. Federal income tax withholding, from the 2026 Publication 15-T percentage method, takes $123.85. Social Security takes 6.2% of gross, $107.31, and Medicare 1.45%, $25.10. New York withholds $70.50 under its brackets and deductions. The net deposit is $1,404.01, 81.1% of gross; over the year that is $36,504 from $45,000, an effective rate of 18.9% on all taxes together. Every line is reproducible from the documents on the sources page, and the table below lists them in the order they appear on a stub.

Two things on that stub are not obvious from the totals. First, the federal line is withholding, not tax: the tables annualise this paycheck as if all 26 were identical, and the year's actual tax, $3,220, differs from the $3,220 withheld by $0, which becomes a refund in April. Second, Social Security and Medicare are the same fraction of every paycheck of the year, because the salary is under the wage base, and no form can change them; only Section 125 deductions reduce their base. The reading guide walks each line and names what it should equal.

Nearby salaries: what $25,000 to $80,000 leave in New York

A raise or a job offer is rarely at the round number on this page, so here is the ladder around it: the same every two weeks paycheck at 6 salaries from $25,000 to $80,000, single, standard W-4, no deductions. The effective rate climbs from 14.2% to 23.3% across the range because federal income tax is progressive while FICA is flat; each extra $10,000 of salary leaves less than the last, and the pay raise calculator prices any step exactly. The salary after tax pages carry the full range, one page per amount.

Reading the ladder the other way answers the interview question: to take home $10,000 more a year in New York takes a raise of roughly $13,032 in gross at this level, because the new dollars are taxed at the marginal rate rather than the average. The state column grows faster than the salary, since New York's brackets rise with income; the FICA column grows in a straight line until the wage base. The gross-up calculator runs the reverse computation for any net.

The same paycheck under each filing status

Filing status is the one W-4 line everyone fills in, and it moves the federal line more than most people expect. On $45,000 in New York, paid every two weeks, a single filer is withheld $123.85 per paycheck; married filing jointly (one income) $49.23, because the joint table doubles the standard deduction to $32,200 and widens every bracket; head of household $82.62, with its $24,150 deduction and its own brackets. Married filing separately uses the single table. New York's own deductions and brackets follow the state’s own joint schedule, which is why the state column moves too. Picking «married» with two incomes and skipping step 2 is the commonest cause of an April bill; the W-4 guide covers the choice.

The last column shows why the status matters beyond the paycheck: the year's federal income tax on $45,000 is $3,220 single and $1,280 married filing jointly on one income, a difference of $1,940 that the W-4 status either delivers through the year or holds back for a refund. Head of household is the status most often missed by single parents, who leave $1,072 a year on the single table. FICA is identical in every row, since it has no status.

The whole year on $45,000: withholding, tax due, and the settlement

26 paychecks of $1,730.77 withhold $3,220 of federal income tax over 2026. The tax actually due on the return, with the $16,100 standard deduction and no credits, is $3,220, so the year ends with a refund of about $0 — the gap between the withholding tables' approximation and the exact computation. The marginal rate on the last dollar is 12%; the effective rate on all taxes together is 18.9%. Social Security applies to every paycheck of the year, because $45,000 is under the $184,500 wage base. The 2026 deductions for overtime premium and tips apply at filing to anyone with qualifying pay; they do not change these paychecks. New York takes $1,833 for the year, 4.1% of salary.

Refund or bill: what the year settles

Withholding is a prepayment; the return computes the tax and returns or collects the difference. On $45,000 with these settings the year withholds $3,220 against $3,220 due, so the settlement is a refund of about $0. A refund is money lent to the Treasury at no interest for up to sixteen months; a bill is fine up to a point and penalised beyond it. The point is the safe harbour: withholding of at least 90% of this year's tax ($2,898 here) or 100% of last year's (110% above $150,000 of income) avoids the underpayment penalty, which is interest on each quarter's shortfall. These paychecks clear the 90% harbour on their own.

What makes the settlement move: credits the W-4 does not carry (the earned income credit, education credits, the 2026 overtime and tip deductions), which enlarge the refund; a second income, other income, or too many dependents on the form, which produce the bill; a bonus withheld at the flat 22% when the marginal rate is 12%, which over-withholds at this salary; and a change of job or a partial year, which annualises each paycheck wrongly. The W-4 fixer sets the lines that bring the settlement to zero, or to a chosen refund.

What deductions do to this paycheck

Deductions are where the same salary produces different paychecks. A 6% traditional 401(k) contribution — $103.85 per paycheck on $45,000, well under the $24,500 annual limit — reduces federal and state taxable wages but not FICA wages, so it costs $85.77 of take-home rather than its face value. A $150 Section 125 deduction for health premiums or an HSA reduces every base including FICA, and costs $112.42. A Roth contribution of the same 6% comes out after tax and costs the full amount now in exchange for tax-free withdrawals later. The table gives each case for this paycheck; the pre-tax deductions calculator runs any amount and the 401(k) calculator draws the whole curve.

The order matters on the stub as well as in the arithmetic. Section 125 items come off first and reduce the FICA wages line, which is why a health premium lowers the Social Security and Medicare figures by 7.65% of itself; the 401(k) comes off next and reduces federal taxable wages only. Both appear in the W-2: box 1 (federal wages) is gross minus both, boxes 3 and 5 (Social Security and Medicare wages) are gross minus the Section 125 items alone. An employer match, where there is one, is added on top of the contribution and never touches the paycheck; the compare two jobs tool values it.

What each W-4 line does to this paycheck

The federal line is the only tax on the stub that a form can change, and each step of the W-4 moves it by a predictable amount. One qualifying child on step 3 lowers withholding by $84.62 per paycheck — the $2,200 credit spread over 26 paychecks — taking the net to $1,488.63. Checking box 2(c) for a second job raises it by $87.11, because the checkbox table halves the brackets so that each job is withheld as if it earned half the household income. Extra withholding on 4(c) is dollar for dollar. Other income on 4(a) adds the tax on it at the marginal rate; deductions on 4(b) remove it. The table runs each case for $45,000 in New York; the W-4 fixer computes the combination that makes the year's withholding equal the year's tax.

None of these lines changes the tax; they change when it is paid. Claiming a child that is not yours on step 3, or deductions you will not take on 4(b), enlarges every paycheck and produces the same amount plus a penalty in April. The lawful levers are the ones you are entitled to — the children you have, the deductions you will itemise, the second income you must account for — and the fixer applies exactly those. A new W-4 takes effect from the next payroll run after your employer receives it, and the year-to-date withholding already taken is not recomputed.

Common mistakes

Checking box 2(c) on one W-4 but not the spouse's, which under-withholds the household. Putting the same children on both W-4s. Using allowances from the old form on a job that has a second income in the household. Claiming exempt to «get more now» — the tax is due in April regardless.

Reading the flat 22% on a bonus as the tax on it. It is withholding; the tax is your marginal rate. Budgeting from the wrong paycheck: biweekly and semi-monthly differ by about 7.7%. Claiming the same child on two W-4s, which under-withholds the household by the credit. Assuming a raise can push you into a bracket that leaves you worse off — in a progressive system it cannot. Forgetting the Social Security cap: above $184,500 the later paychecks are larger, and a budget built on January's paycheck is too tight for December's.