Paycheck Calculator

Worked example

$3,500 semi-monthly gross with 22% federal, 6% state, $200 401(k), and YTD $42,000 → FICA applies on full check until Social Security wage base; estimated take-home often lands near $2,300–$2,450 depending on rates.

When to use this

• Estimating take-home after a raise, promotion, or job change.
• Seeing how 401(k), HSA, or health premiums change net pay.
• Planning cash flow when overtime or a bonus lands in one check.
• Comparing biweekly versus semi-monthly pay on the same annual salary.
• Rough withholding check before updating your W-4 allowances.

Common examples

• $2,400 biweekly + $600 overtime in one check → higher withholding spike.
• $5,000 monthly with 8% 401(k) pre-tax → take-home drops but retirement contributions are deferred.
• Two jobs: run each paycheck separately—combined withholding may need W-4 adjustment.
• $1,800 weekly gross in Texas (no state income tax) vs California—state rate changes take-home sharply.
• Semi-monthly $3,500 with YTD $85,000 → Social Security still applies until wage base is reached.

Common mistakes

• Treating flat tax percentages as exact IRS withholding.
• Forgetting YTD gross when checking Social Security wage-base limits.
• Assuming overtime is taxed at a special flat rate on every paycheck.
• Mixing pre-tax and post-tax deductions in the same field.
• Using one check estimate as monthly cash flow without multiplying by pay periods.

How it works

Enter gross pay for one paycheck, pay frequency, optional year-to-date gross, and flat federal/state tax rates. FICA is applied automatically: Social Security at 6.2% (capped by the annual wage base using YTD wages) and Medicare at 1.45%. Other flat deductions are subtracted to estimate take-home pay.

Limitations

This is a simplified educational payroll-withholding estimate that includes employee FICA (Social Security and Medicare). It is not a full payroll system and does not model every filing-status rule, credit, benefit, or employer-specific setting. Confirm amounts with your payroll provider or a tax professional.

Privacy and file handling

Your data stays on your device and is not uploaded.

Accuracy & methodology

This section documents how the calculator works, what it leaves out, and when results were last reviewed. Figures are educational estimates—not professional advice—and are not labeled "current" unless tied to automatically updated reference data.

Formula source or methodology

Take-home = gross pay − (federal % + state % + other deductions). Percent deductions apply to gross; flat deductions subtract after percents.

Jurisdiction

United States (highly simplified)

Unit system

Currency per paycheck

Rounding method

Currency amounts round to two decimal places (half up via Math.round × 100 / 100).

Assumptions

• Single paycheck period; user supplies deduction percentages or flat amounts
• Percent fields are simple fractions of gross, not bracket tables

Known omissions

• Not tax, legal, investment, or lending advice. Confirm material decisions with qualified professionals.
• Federal income tax brackets, standard deduction, and credits for any tax year
• State and local income taxes
• Filing status (single, married, head of household, etc.)
• Payroll taxes (FICA, Medicare surtax) and self-employment tax
• Alternative Minimum Tax (AMT) and net investment income tax
• Capital gains preferential rates
• Pre-tax vs post-tax benefit deductions (401k, HSA, health premiums)
• W-4 withholding tables and IRS Publication 15-T
• Bonus supplemental wage rates

Test cases (automated)

• Gross with 0% deductions equals take-home
• Negative gross is rejected

Version & last verified

Logic version 1.0. Content and formulas last verified 2026-07-24.