Income Tax Calculator

How Income Tax Is Calculated

Start with income included in the estimate, subtract the chosen deduction, apply each progressive bracket to its share of taxable income, then subtract supported credits. Federal and state income taxes are calculated separately. Payroll taxes are excluded from this tool’s total.

Gross income and adjustments: this version accepts annual earned income, plus spouse income for a joint return. It assumes the entered total is the income base for credit phaseouts. It does not calculate every above-the-line adjustment, investment-income category or business deduction.

Standard vs itemized deduction: choose the base standard deduction for your filing status or enter an eligible itemized deduction total. If you choose itemizing, that amount is used even when smaller. The calculator does not determine whether each expense is deductible or apply every limit.

Taxable income is the income remaining after the selected deduction, floored at zero. Progressive brackets apply different rates to different slices of this amount. A deduction reduces taxable income; a credit reduces calculated tax. The supported child credit is nonrefundable here and phases out with income.

Federal Income-Tax Example

A single filer with $75,000 of ordinary income, the $16,100 base standard deduction and no credits has $58,900 of taxable income. The first $12,400 is taxed at 10% ($1,240), the next $38,000 at 12% ($4,560), and the remaining $8,500 at 22% ($1,870). Estimated federal income tax is $7,670.

The 22% bracket is not applied to the full $75,000. The effective federal rate using gross income is about 10.23%. State taxes are additional where applicable. This example excludes special deductions, credits, AMT and payroll taxes.

Marginal Tax Rate vs Effective Tax Rate

The marginal rate describes the bracket applying to the next dollar of taxable ordinary income. The effective federal rate is federal income tax divided by entered household income. The combined rate adds the estimated state income tax to the numerator.

Rates can change after deductions and credits. Comparing percentages without matching the denominator can be misleading: tax divided by taxable income differs from tax divided by gross income. The main effective rate here uses the entered income total.

Federal vs State Income Tax

States do not simply reuse federal brackets. State deductions, exemptions, credits and benefit treatment may differ. Some states impose no individual wage income tax; others use flat or progressive systems. Local income taxes may add another layer.

The existing state engines contain simplified and fallback estimates that are not yet verified as complete 2026 liability calculations. No new state annual-tax pages are published by this upgrade. Use the federal breakdown independently and verify state liability with the responsible agency.

Income Tax vs Paycheck Withholding

Withholding is a payment toward expected tax, while liability is the tax calculated for the year. Your refund or amount due depends on comparing liability with withholding, estimated payments and applicable refundable credits. This calculator does not estimate a refund because it does not collect all those inputs.

Use the Paycheck Calculator to estimate a particular payroll payment. Changing a W-4 changes payroll prepayments; it does not by itself change the underlying annual income or statutory brackets.

Why Your Tax Return May Differ

This model covers ordinary earned income, a base or entered deduction and the nonrefundable qualifying-child credit. It assumes users meet credit eligibility requirements and that entered income equals the relevant phaseout income.

It excludes AMT, preferential capital-gain rates, refundable credits, age/blindness additions, dependent standard-deduction restrictions, and high-income itemized-deduction limitations. The final return can also include other income and adjustments. It does not prepare or file taxes.