Single
Married Filing Jointly
Married Filing Separately
Head of Household
Estimated State Income Tax
$0.00
Understanding State Income Tax
State income tax is a tax levied by many U.S. states on the income earned by their residents and, in some cases, on income earned within the state by non-residents. The rules for calculating state income tax vary significantly from state to state. Some states have no income tax at all, while others have complex progressive tax brackets or flat tax rates.
How This Calculator Works
This calculator provides an *estimated* state income tax liability. It simplifies the complex tax laws of various states into a general framework. The calculation typically involves the following steps:
Determine Adjusted Gross Income (AGI): This calculator starts with your provided Annual Gross Income. In real-world scenarios, AGI is calculated by subtracting certain "above-the-line" deductions from your gross income. For simplicity, we've omitted this initial step and assume gross income is the starting point before state-specific adjustments.
Calculate Taxable Income: Your Taxable Income is generally your AGI minus your Deductions. Deductions can be standard or itemized. This calculator uses a single input for total deductions.
Apply Tax Rates: Taxable income is then subject to the state's tax rates. States may have:
Progressive Tax Brackets: Higher income levels are taxed at higher rates.
Flat Tax: A single tax rate applies to all taxable income.
No Income Tax: Some states have no state income tax.
This calculator uses a simplified model. It assumes a general progressive tax structure for demonstration purposes, but the actual rates and brackets will vary by state.
Subtract Tax Credits: Finally, Tax Credits are subtracted directly from the calculated tax liability. Tax credits are generally more valuable than deductions as they reduce your tax dollar-for-dollar.
Important Considerations:
State Variation: This calculator does NOT represent any specific state's tax law. Tax laws are complex and differ greatly. You MUST consult your specific state's Department of Revenue or a tax professional for accurate calculations.
Filing Status: Your filing status (Single, Married Filing Jointly, etc.) impacts standard deductions and tax brackets in most states.
Deductions and Credits: The types of deductions and credits available are extensive (e.g., dependent credits, child care credits, mortgage interest, state/local taxes (SALT) deduction limitations). This calculator uses simplified inputs.
Other Taxes: This calculator only addresses income tax. States may also have sales tax, property tax, and other levies.
Professional Advice: This tool is for educational and estimation purposes only. It is not a substitute for professional tax advice.
function calculateStateTax() {
var grossIncome = parseFloat(document.getElementById("grossIncome").value);
var filingStatus = document.getElementById("filingStatus").value;
var deductions = parseFloat(document.getElementById("deductions").value);
var credits = parseFloat(document.getElementById("credits").value);
var resultValueElement = document.getElementById("result-value");
// Basic validation
if (isNaN(grossIncome) || isNaN(deductions) || isNaN(credits) || grossIncome < 0 || deductions < 0 || credits < 0) {
resultValueElement.textContent = "Invalid input. Please enter valid numbers.";
resultValueElement.style.color = "#dc3545"; // Red for error
return;
}
// — Simplified State Tax Calculation Logic —
// This is a highly generalized model. Real state taxes involve specific brackets,
// exemption amounts, and phase-outs which vary drastically.
// We'll use a hypothetical progressive rate structure for demonstration.
var taxableIncome = grossIncome – deductions;
if (taxableIncome < 0) {
taxableIncome = 0; // Taxable income cannot be negative
}
var calculatedTax = 0;
// Hypothetical Tax Brackets (Example – NOT REAL STATE DATA)
// These brackets and rates are illustrative and for demonstration only.
if (filingStatus === "single") {
if (taxableIncome <= 10000) {
calculatedTax = taxableIncome * 0.02; // 2%
} else if (taxableIncome <= 40000) {
calculatedTax = (10000 * 0.02) + ((taxableIncome – 10000) * 0.04); // 2% on first 10k, 4% on remainder
} else if (taxableIncome <= 80000) {
calculatedTax = (10000 * 0.02) + (30000 * 0.04) + ((taxableIncome – 40000) * 0.06); // 2% on first 10k, 4% on next 30k, 6% on remainder
} else {
calculatedTax = (10000 * 0.02) + (30000 * 0.04) + (40000 * 0.06) + ((taxableIncome – 80000) * 0.08); // 2%, 4%, 6%, 8%
}
} else if (filingStatus === "married_filing_jointly") {
if (taxableIncome <= 20000) {
calculatedTax = taxableIncome * 0.02; // 2%
} else if (taxableIncome <= 80000) {
calculatedTax = (20000 * 0.02) + ((taxableIncome – 20000) * 0.04); // 2% on first 20k, 4% on remainder
} else if (taxableIncome <= 160000) {
calculatedTax = (20000 * 0.02) + (60000 * 0.04) + ((taxableIncome – 80000) * 0.06); // 2% on first 20k, 4% on next 60k, 6% on remainder
} else {
calculatedTax = (20000 * 0.02) + (60000 * 0.04) + (80000 * 0.06) + ((taxableIncome – 160000) * 0.08); // 2%, 4%, 6%, 8%
}
} else if (filingStatus === "married_filing_separately") {
// Often similar brackets to single but may have lower thresholds
if (taxableIncome <= 10000) {
calculatedTax = taxableIncome * 0.02; // 2%
} else if (taxableIncome <= 40000) {
calculatedTax = (10000 * 0.02) + ((taxableIncome – 10000) * 0.04); // 2% on first 10k, 4% on remainder
} else if (taxableIncome <= 80000) {
calculatedTax = (10000 * 0.02) + (30000 * 0.04) + ((taxableIncome – 40000) * 0.06); // 2% on first 10k, 4% on next 30k, 6% on remainder
} else {
calculatedTax = (10000 * 0.02) + (30000 * 0.04) + (40000 * 0.06) + ((taxableIncome – 80000) * 0.08); // 2%, 4%, 6%, 8%
}
} else if (filingStatus === "head_of_household") {
// Often wider brackets than single
if (taxableIncome <= 15000) {
calculatedTax = taxableIncome * 0.02; // 2%
} else if (taxableIncome <= 60000) {
calculatedTax = (15000 * 0.02) + ((taxableIncome – 15000) * 0.04); // 2% on first 15k, 4% on remainder
} else if (taxableIncome <= 120000) {
calculatedTax = (15000 * 0.02) + (45000 * 0.04) + ((taxableIncome – 60000) * 0.06); // 2% on first 15k, 4% on next 45k, 6% on remainder
} else {
calculatedTax = (15000 * 0.02) + (45000 * 0.04) + (60000 * 0.06) + ((taxableIncome – 120000) * 0.08); // 2%, 4%, 6%, 8%
}
}
// Apply tax credits
var finalTax = calculatedTax – credits;
if (finalTax < 0) {
finalTax = 0; // Tax liability cannot be negative after credits
}
// Display the result, formatted as currency
resultValueElement.textContent = "$" + finalTax.toFixed(2);
resultValueElement.style.color = "#28a745"; // Green for success
}