Determine your taxable income
Identify the applicable tax rate or tax bracket
Subtract deductions from gross income
Subtract tax credits from the calculated tax
Multiply taxable income by the tax rate if using a flat tax
Use each bracket rate on the portion of income within that bracket if using progressive tax
Add all bracket amounts together
Subtract withholding or estimated tax payments already made
Add any additional taxes owed
Compare the result to zero
If the result is positive, that is tax owed
If the result is negative, that is a refund amount
Review local, state, and federal tax rules separately
Include self-employment tax, sales tax, or payroll tax if applicable