Public conceptDeductions and rates
Standard deduction
A fixed deduction available to many filers instead of itemizing eligible expenses.
In one sentence
The standard deduction removes a portion of included income before rates are applied.
Model
gross included income − deduction applied = taxable income
Worked example
A single filer in this 2025 model begins with a $15,750 standard deduction, limited to the income available to shelter.
What to notice
Follow this mechanism in a related lesson, where the same calculator engine exposes every intermediate value.
Common misconception
A deduction reduces income exposed to rates; it is not a dollar-for-dollar payment of tax.
See it in motion