Most people never check. Type the numbers off your pay stub and this will tell you whether the math holds — and exactly what to ask your employer if it doesn't.
Earnings
Taxes Withheld
Other Deductions
Health/dental/vision — lowers FICA
Union dues, garnishments, HSA…
Improves accuracy for high earners
Some payroll numbers follow fixed rules, so they can be checked exactly. Others depend on choices only you and your employer know. This tool sticks to the first group.
| Line | Rule | Checkable? |
|---|---|---|
| Social Security | Exactly 6.2%, stops at the annual wage cap | Yes — exact |
| Medicare | 1.45%, no cap, +0.9% on high wages | Yes — exact |
| Net pay | Gross minus every deduction | Yes — arithmetic |
| Gross (hourly) | Rate × hours, overtime at 1.5× | Yes — arithmetic |
| Federal income tax | Depends on your W-4 elections | No — context only |
| State income tax | Varies by state and state form | Partly |
Reading every line first helps — our pay stub guide explains each abbreviation, and the abbreviation cheat sheet decodes the codes.
How do I know if my paycheck is correct?
Check the parts that follow fixed rules. Social Security must be 6.2% of your FICA wages and Medicare 1.45%, overtime is normally 1.5x your rate beyond 40 hours a week, gross should equal your rate times your hours, and gross minus every deduction must equal your net pay. This tool checks all of those at once.
My Social Security deduction looks wrong. What causes that?
Most often pre-tax insurance, which lowers the wages Social Security is charged on, or hitting the annual wage cap after which the deduction stops entirely. If neither applies, the percentage should be exactly 6.2% and a mismatch is worth raising with payroll.
Why is no federal income tax being withheld from my paycheck?
That is usually a W-4 outcome rather than a mistake — low earnings, dependents claimed in Step 3, or an exempt claim will all produce $0. It is not an error by itself, but if it runs all year you may owe when you file.
What should I do if my paycheck is wrong?
Start with payroll or HR and ask them to walk through the specific line. Bring the stub and the figure you expected. Most discrepancies are data-entry or setup issues that are corrected on the next run. If pay was genuinely withheld or overtime unpaid, your state labor department and the US Department of Labor handle wage complaints.
Does this tool see my pay information?
No. Everything is calculated inside your browser and nothing is uploaded, stored, or shared. Closing the tab discards it.