Free Paycheck Calculator (+ Guide)

What is a paycheck calculator?

A paycheck calculator turns your gross pay into take-home pay by taking out the taxes and deductions your employer withholds.

This one follows the IRS's own withholding method for 2026, so the federal number matches what a payroll system works out from the same W-4.

How it works

Everything is worked out in your browser.

How federal withholding is worked out

Publication 15-T gives employers with payroll software one worksheet, Worksheet 1A, and the calculator runs it.

• Annualize: your taxable wages a paycheck × the paychecks in a year, plus any other income from W-4 Step 4(a)
• Subtract: your deductions from Step 4(b), plus $8,600 ($12,900 if married filing jointly) when the Step 2 box isn't checked
• Look up: the 2026 table for your filing status gives a base amount plus a percentage of what's over the row's start
• Divide and credit: split it over your paychecks, then take off your Step 3 credits a paycheck and add any Step 4(c) extra

Publication 15-T lets employers round the tax to the nearest dollar, so your stub can differ by a few cents.

Social Security and Medicare

Publication 15 sets the 2026 rates every employer withholds, called FICA.

• Social Security: 6.2% of your wages, up to a wage base of $184,500 for 2026
• Medicare: 1.45% of all your wages, with no limit
• Additional Medicare Tax: another 0.9% on wages over $200,000 in a calendar year, from the employee only

When your pay passes the wage base, Social Security stops for the rest of the year. The calculator spreads that evenly over your paychecks.

Pre-tax deductions

Publication 15's table of special rules shows which taxes each deduction escapes.

• 401(k) contributions: generally exempt from federal income tax withholding, but still taxed for Social Security and Medicare
• Health insurance through a cafeteria plan (section 125): treated as a nontaxable benefit, so it's left out of all three

So $100 to a 401(k) lowers your take-home pay by less than $100, since part of it would have gone to income tax.

State and local tax

Each state taxes wages its own way, and some don't tax them at all, so the calculator takes your own rate. Type your state and local rate, or 0 if your state has no income tax.

A worked example

Here's the example the calculator loads: a $65,000 salary paid every 2 weeks, single, with $125 to a 401(k), $60 of health insurance and a 4.5% state rate.

Gross pay is $2,500.00 a paycheck. Without the health insurance, Social Security and Medicare wages are $2,440.00; without the 401(k) too, income tax wages are $2,315.00.

Worksheet 1A: $2,315.00 × 26 = $60,190.00, minus $8,600 = $51,590.00. The 2026 single table gives $1,240 + 12% of the amount over $19,900 = $5,042.80 a year, or $193.95 a paycheck.

Social Security is $151.28, Medicare $35.38 and the state $104.17, so the take-home pay is $1,830.21 a paycheck, or about $47,585.49 a year.

Mistakes to avoid

These are the slips that come up most.

• Using your tax bracket as your withholding rate, when only the top slice of pay is taxed at it
• Forgetting that a 401(k) still pays Social Security and Medicare
• Leaving the Step 2 box unchecked when you have two jobs, which can mean too little withheld

Who is the paycheck calculator for?

It's for anyone checking a pay stub, weighing a job offer or deciding how much to put in a 401(k), and these tools help around it.

• Hourly to salary calculator – to compare pay rates
• Retirement calculator – for what the 401(k) grows to
• Tax rates by country – for pay outside the US

Check your W-4 once a year, and your paycheck holds no surprises in April.