The FICA tax calculator above shows exactly what gets withheld from a W-2 paycheck for Social Security and Medicare β the two payroll taxes that together make up FICA, short for the Federal Insurance Contributions Act. Enter your annual wages and filing status to see your Social Security withholding, your Medicare withholding, any additional Medicare tax owed at higher income, and what your employer contributes on your behalf.
Most employees glance at their pay stub, see a line labeled "FICA" or "Social Security/Medicare," and never think much more about it. But understanding exactly how those numbers are calculated matters β whether you're checking that your employer withheld the right amount, comparing a job offer's take-home pay, or trying to understand why your paycheck shrinks a little less once you cross a certain income level. This is one of several free planning tools Arb Digital built to make tax math approachable for everyday people, not just accountants.
What This FICA Tax Calculator Does
This tool applies the same rates the IRS and Social Security Administration use to calculate payroll tax withholding: 6.2% for Social Security (up to the annual wage base) and 1.45% for Medicare (with no cap), plus an additional 0.9% Medicare tax once your wages cross a threshold based on your filing status. It totals your withholding into one number, breaks each piece out individually, and also shows the employer match β the amount your employer pays in on top of your withholding, which is required by law but never appears on your pay stub.
How to Use It
- Enter your annual wages. Use your total gross W-2 wages for the year β the number before taxes, retirement contributions, or other deductions are taken out.
- Choose your filing status. This only changes the income threshold at which the additional 0.9% Medicare tax applies.
- Click Calculate to see your total FICA withholding, the Social Security and Medicare breakdown, and your employer's matching contribution.
The Formula β How FICA Tax Is Calculated
Social Security tax is 6.2% of your wages, but only up to the annual Social Security wage base β a ceiling set each year by the Social Security Administration (illustratively $176,100 for 2025 in this calculator; confirm the current figure at SSA.gov). Once your wages for the year exceed that ceiling, no further Social Security tax is withheld for the rest of the year β which is why very high earners sometimes notice their take-home pay jump slightly late in the year.
Medicare tax is 1.45% of all your wages, with no ceiling at all β every dollar you earn is subject to it. On top of the base Medicare rate, an additional 0.9% Medicare tax applies to wages above $200,000 for single filers and heads of household, or $250,000 for married couples filing jointly (with a $125,000 threshold for married filing separately), a rule described by the IRS at IRS.gov. Unlike Social Security and the base Medicare rate, the additional Medicare tax is not matched by your employer β it's an employee-only tax. Adding the Social Security tax, base Medicare tax, and any additional Medicare tax together gives your total FICA withholding for the year.
Why Your Employer Pays a Matching Amount Too
FICA is a shared tax by design. For every dollar of Social Security and base Medicare tax withheld from your paycheck, your employer pays a matching amount out of its own funds β 6.2% for Social Security (up to the wage base) and 1.45% for Medicare, with no separate line item on your pay stub to show it. Combined, employee and employer contributions add up to the full 15.3% (12.4% Social Security + 2.9% Medicare) that funds Social Security retirement, disability, and survivor benefits, along with Medicare hospital insurance.
This matching structure is the exact reason self-employed people pay noticeably more in payroll-style taxes than W-2 employees on the same income β a self-employed person has no employer to split the bill with, so they cover both the employee and "employer" halves themselves through self-employment tax. If you're comparing a W-2 offer against 1099 or self-employed income, seeing the employer match here β money that's being paid on your behalf but never touches your paycheck β helps make that comparison more accurate. Our self employment tax calculator shows the equivalent calculation for self-employed earners.
What Happens Near the Social Security Wage Base
If your annual wages are close to or above the Social Security wage base, it's worth understanding what happens at the cap. Say the wage base sits at $176,100 for the year and you earn $200,000. Social Security tax (6.2%) only applies to the first $176,100 β the remaining $23,900 is Social Security-tax-free, though it's still fully subject to the uncapped 1.45% Medicare tax. This is one reason higher earners sometimes see their per-paycheck take-home amount tick up slightly in the final pay periods of the year, once their year-to-date wages cross the cap and Social Security withholding stops for the rest of the year.
Multiple Employers in One Year
The Social Security wage base cap applies per person across the year, not per employer. If you switch jobs mid-year, each new employer starts withholding Social Security tax from zero, regardless of what your previous employer already withheld β which means it's possible, in aggregate, for more than the maximum Social Security tax to be withheld across your combined paychecks. If that happens, the excess is refundable, and you claim it as a credit on your federal income tax return when you file. Keeping your final pay stub from each employer makes this easy to reconcile at tax time.
Checking Your Pay Stub Against This Calculator
If you want to verify that your employer is withholding the correct amount, this calculator is a useful cross-check β but remember it works from an annual projection, while your pay stub shows a single pay period. To compare accurately, look at your year-to-date figures on a recent pay stub rather than one isolated paycheck; most stubs show cumulative Social Security and Medicare withholding for the year alongside the current period's amount. If your year-to-date Social Security withholding is tracking noticeably above or below 6.2% of your year-to-date wages (once you account for the wage base cap), or your Medicare withholding isn't close to 1.45% of your total wages, it's worth flagging to your payroll or HR department β small early-year errors are far easier to correct than a discrepancy discovered in December.
It's also worth remembering that FICA withholding is calculated independently from federal income tax withholding, which is based on the information you provide on your Form W-4, not on a flat percentage. A change to your W-4 β claiming more or fewer allowances, or adjusting for a second job β will change your income tax withholding, but it has no effect on your FICA withholding, which is fixed by statute regardless of what you put on that form.
Arb Digital builds fast, high-converting websites and marketing systems for freelancers and small businesses β check out our other free tax planning tools.
Try the Self Employment Tax Calculator All Free ToolsCommon Mistakes to Avoid
- Confusing FICA with federal income tax. FICA covers only Social Security and Medicare β federal income tax withholding is calculated separately using a different formula entirely.
- Assuming Medicare tax has a cap like Social Security does. Only Social Security tax stops at the wage base; Medicare tax applies to 100% of wages with no ceiling.
- Forgetting the additional Medicare tax at higher income. Employers are required to withhold the extra 0.9% once your wages from that employer cross $200,000, regardless of your actual filing status or household income.
- Not reconciling multiple employers. If you had more than one job in a year and combined wages exceeded the wage base, you may be owed a refundable Social Security tax credit.
- Overlooking the employer match when comparing income sources. The employer's matching contribution is real compensation cost that doesn't show up on your pay stub but is part of the full picture when comparing W-2 to 1099 income.
Related Free Tools From Arb Digital
If you also have self-employment or 1099 income, check the self employment tax calculator and 1099 tax calculator for the equivalent breakdown, plan estimated payments with the quarterly tax calculator, or estimate your overall federal tax with the income tax calculator. Explore every calculator in our free online tools hub.
Frequently Asked Questions
FICA stands for the Federal Insurance Contributions Act, the law that requires Social Security and Medicare taxes to be withheld from wages and matched by employers.
The combined employee FICA rate is 7.65% β 6.2% for Social Security (up to the annual wage base) and 1.45% for Medicare (with no cap), plus an additional 0.9% Medicare tax above certain income thresholds.
Yes. Your employer matches your 6.2% Social Security and 1.45% Medicare contributions dollar-for-dollar, though it does not match the additional 0.9% Medicare tax, which is employee-only.
Yes. Social Security tax only applies up to the annual wage base, illustratively set at $176,100 for 2025 in this calculator. Medicare tax has no such cap.
It's an extra 0.9% Medicare tax that applies to wages above $200,000 for single filers and heads of household, or $250,000 for married couples filing jointly, on top of the standard 1.45% rate.
If you had multiple employers and your combined Social Security withholding exceeded the annual maximum because each employer withheld independently, the excess is refundable as a credit on your federal income tax return.
This tool provides general estimates for educational purposes only and is not financial, tax, legal, or medical advice. Figures are illustrative; consult a licensed professional for decisions.
