State Income Tax Estimator Formula

Understand the math behind the state income tax estimator. Each variable explained with a worked example.

Use the State Income Tax Estimator

Formulas Used

Estimated State Tax

state_tax = taxable_income * state_rate / 100

Monthly State Tax

monthly_state_tax = taxable_income * state_rate / 100 / 12

Income After State Tax

after_state_tax = taxable_income * (1 - state_rate / 100)

Variables

VariableDescriptionDefault
taxable_incomeTaxable Income(USD)75000
state_rateState Tax Rate(%)5

How It Works

State Income Tax

State income tax rates vary widely. Some states have no income tax while others charge over 13%.

No Income Tax States

Alaska, Florida, Nevada, New Hampshire (dividends only), South Dakota, Tennessee (dividends only), Texas, Washington, Wyoming

Highest Tax States

California (up to 13.3%), Hawaii (up to 11%), New York (up to 10.9%)

Worked Example

$75,000 income in a state with 5% flat rate.

taxable_income = 75000state_rate = 5
  1. 01State tax = $75,000 x 5% = $3,750
  2. 02Monthly = $3,750 / 12 = $313

Ready to run the numbers?

Open State Income Tax Estimator