What your paycheck and tax brackets really say

A long read

Before we start

This module is about the United States: federal and state income tax, FICA, the W-4, and the seven US brackets. The ideas travel — gross against net pay, marginal rates, a refund being your own money back — but the names, the rates and the forms do not. If you are paid in another country, read it for how the machinery works, not for the numbers.

Sources

IRS — Federal income tax rates and brackets; the marginal-rate structure
IRS Publication 15 (Circular E) — federal income tax withholding
Social Security Administration — the 6.2% Social Security and 1.45% Medicare employee rates (FICA), and the annual wage base
Tax Foundation — state income tax rates, including the states with none

Read end to end and corrected: August 8, 2026. Numbers checked: August 8, 2026.