The Standard Deduction Explained (2025)

Before any tax bracket touches your income, the standard deduction takes a chunk off the top tax-free. It’s the simplest, most valuable tax break most Americans get — and it’s why your taxable income is lower than your salary.

2025 standard deduction amounts

• Single: $15,000
• Married filing jointly: $30,000
• Head of household: $22,500
• Married filing separately: $15,000

Standard vs itemised

You can either take the standard deduction or itemise (add up specific deductions like mortgage interest, state/local taxes up to the cap, and charitable gifts) — whichever is larger. Since the standard deduction nearly doubled in 2018, the large majority of filers now take it because their itemised total wouldn’t beat it.

How it fits the calculation

Your federal tax is worked out on taxable income = salary − pre-tax contributions − standard deduction. Only that remaining amount runs through the tax brackets. It’s a big reason your effective tax rate is lower than your bracket.

See it applied

Our US calculator applies the standard deduction automatically — enter your salary to see your taxable income and the resulting federal tax.