Glossary term

Average tax rate

Average tax rate compares total tax with the income amount used as the denominator.

Plain meaning

What average tax rate means

Average tax rate is a ratio. It divides total tax by a stated income base, such as taxable income or another income amount identified by the calculator.

Formula role

How OpenBook uses it

Tax calculators may show average tax rate as a summary measure after tax is estimated. It helps describe the whole estimate, while marginal tax rate describes the next dollar or selected additional amount.

Common confusion

The denominator matters

Average tax rate can change depending on whether the denominator is taxable income, gross income, net income, or another amount. OpenBook calculators state the income base used where the term appears.