2022 and 2023 federal income tax brackets by filing statusBelow are the federal income tax brackets for single filers, heads of household, and married people who file either jointly and separately for 2021 and 2022.
Your marginal tax rate is the highest tax rate your taxable income falls into.
For one thing, it's because you can only determine your effective tax rate by going through the machinations of figuring out your marginal tax rate and the resulting total tax liability.
Once you know your marginal tax bracket, you know how much tax you'll pay on each dollar of income.
You can then calculate your effective tax rate based on your total tax liability for the year.