There are seven federal tax brackets for the 2020 tax year:
Your bracket depends on your taxable income and filing status. You only pay taxes on your taxable income.
To determine your taxable income, you need to subtract any adjustments from your gross income. Adjustments to Income include such items as Educator expenses, Student loan interest, Alimony payments or contributions to a retirement account. Then once you determine your adjusted gross income (AGI), subtract any deductions you might be entitled to and that number is your taxable income. These are the rates for taxes due in April 2021.
Tax brackets and rates for previous years, are elsewhere on this website.