How federal tax brackets work
The US federal income tax is progressive: income is divided into bands, and each band is taxed at its own rate. For 2024 the seven rates are 10%, 12%, 22%, 24%, 32%, 35% and 37%. You do not pay your top rate on all your income — only on the slice that falls inside that top band.
Your marginal rate is the rate on your last dollar — the highest band you reach. Your effective rate is your total tax as a share of taxable income, and it is always lower than the marginal rate.
Worked example
A single filer with $75,000 of taxable income in 2024:
Taxable income vs. gross income
Brackets apply to taxable income, which is your gross income minus the standard deduction (or itemized deductions) and other adjustments. For 2024 the standard deduction is $14,600 for single filers, $29,200 for married filing jointly and $21,900 for head of household. Subtract that from your gross pay before entering a number here for the most accurate result.