How Your Paycheck Is Calculated
Your gross pay — what you earn before any deductions — is determined by your salary or hourly rate and how many hours you work. What actually lands in your bank account (net pay) is significantly less, reduced by federal income tax withholding, FICA taxes (Social Security and Medicare), state income taxes, and any pre-tax benefit deductions you have elected.
Federal Income Tax Withholding
Employers withhold federal income tax from each paycheck based on your W-4 elections and the IRS withholding tables. This calculator uses the 2024 federal tax brackets and standard deduction to estimate per-paycheck federal withholding. Your actual withholding may differ based on additional W-4 adjustments, extra withholding requested, or credits you've claimed. The IRS Tax Withholding Estimator (irs.gov) provides the most accurate result for complex situations.
FICA Taxes: Social Security and Medicare
FICA (Federal Insurance Contributions Act) taxes fund Social Security and Medicare:
- Social Security: 6.2% of wages up to the 2024 wage base of $168,600. Earnings above this limit are not subject to Social Security tax.
- Medicare: 1.45% on all wages, with no cap. Higher earners (over $200,000 for single filers) also owe an Additional Medicare Tax of 0.9%, though this is typically reconciled at tax filing rather than withheld by default.
Your employer matches these contributions dollar-for-dollar — you pay 7.65% and so does your employer, for a total of 15.3% contributed to FICA on your behalf.
Pre-Tax Deductions: Your Best Tool for Increasing Take-Home Pay
Pre-tax deductions reduce your taxable income before federal and state taxes are calculated, making them dollar-for-dollar tax savings. Common pre-tax deductions include:
- Traditional 401(k) or 403(b) contributions: Up to $23,000 in 2024 ($30,500 if age 50+), contributed pre-tax to your retirement account.
- Health insurance premiums: Your share of employer-sponsored health, dental, and vision insurance is typically deducted pre-tax through a Section 125 (cafeteria) plan.
- Health Savings Account (HSA): Contributions to an HSA (for those with a qualifying high-deductible health plan) are pre-tax and can be used for medical expenses tax-free.
- Flexible Spending Account (FSA): Pre-tax contributions for healthcare or dependent care expenses, up to annual IRS limits.
State Income Tax
State income tax rates vary widely. Nine states have no income tax on wages: Alaska, Florida, Nevada, South Dakota, Tennessee, Texas, Washington, Wyoming, and New Hampshire (which taxes only interest and dividends, not wages). States with flat income taxes include Colorado (4.4%), Illinois (4.95%), Michigan (4.25%), and Pennsylvania (3.07%). States like California, New York, and Oregon use graduated brackets with top rates exceeding 9–13% for high earners. Enter your state's approximate rate for the most relevant estimate.
Understanding Your Effective Tax Rate
The sum of federal income tax, Social Security, Medicare, and state income tax represents your total tax burden. A common surprise for new workers is how much of the gross paycheck is withheld. Someone earning $75,000 annually and paying bi-weekly might see effective total withholding of 22–28% depending on their state and deductions. The good news: pre-tax contributions to a 401(k) and health insurance meaningfully reduce that burden and simultaneously build retirement security and health coverage.