Pay stub checker
Copy the numbers from your pay stub. We recompute every line with the official 2026 formulas and tell you which lines don't match, and the most likely reason why.
Assumptions: W-4 from 2020 or later with no Step 3 or Step 4 entries, the state's usual default allowances, no local tax. Nothing you type leaves your browser.
Common reasons a pay stub doesn't match
Why is my federal withholding higher than expected?
The most common reasons are the W-4 Step 2 box (two jobs or a working spouse), extra withholding in Step 4(c), a bonus or commission in this check withheld at the flat 22% rate, or an employer still using an old (pre-2020) W-4 with fewer allowances.
Why is there no Social Security on my pay stub?
Either you have already earned more than the Social Security wage base this year ($184,500 in 2026, $192,300 in 2027), or you work for an employer or in a job that is exempt, such as some state and local government jobs with their own pension plan.
Do 401(k) contributions lower Social Security and Medicare?
No. Traditional 401(k) deferrals lower federal income tax (and most states), but Social Security and Medicare are still charged on them. Health insurance, HSA and FSA deductions through a cafeteria plan lower all three.
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