function calculatePayroll() {
// Constants for 2024 (simplified for calculator)
var SS_RATE = 0.062;
var SS_WAGE_BASE = 168600;
var MED_RATE = 0.0145;
var ADD_MED_RATE = 0.009;
var PA_STATE_TAX_RATE = 0.0307; // Pennsylvania flat tax rate
// Federal Standard Deductions (Annual)
var FED_STD_DEDUCTION_SINGLE = 14600;
var FED_STD_DEDUCTION_MARRIED = 29200;
var FED_STD_DEDUCTION_HOH = 21900;
// Federal Allowance Value (Annual, for percentage method)
var FED_ALLOWANCE_VALUE = 5000;
// Additional Medicare Tax Thresholds (Annual)
var ADD_MED_THRESHOLD_SINGLE = 200000;
var ADD_MED_THRESHOLD_MARRIED = 250000;
var ADD_MED_THRESHOLD_HOH = 200000;
// Get input values
var grossPayPerPeriod = parseFloat(document.getElementById('grossPay').value);
var payFrequencyMultiplier = parseInt(document.getElementById('payFrequency').value);
var fedFilingStatus = document.getElementById('fedFilingStatus').value;
var fedAllowances = parseInt(document.getElementById('fedAllowances').value);
var preTaxDeductionsPerPeriod = parseFloat(document.getElementById('preTaxDeductions').value);
var localTaxRate = parseFloat(document.getElementById('localTaxRate').value);
var postTaxDeductionsPerPeriod = parseFloat(document.getElementById('postTaxDeductions').value);
// Validate inputs
if (isNaN(grossPayPerPeriod) || grossPayPerPeriod < 0) {
alert("Please enter a valid Gross Pay.");
return;
}
if (isNaN(preTaxDeductionsPerPeriod) || preTaxDeductionsPerPeriod < 0) {
alert("Please enter valid Pre-tax Deductions.");
return;
}
if (isNaN(localTaxRate) || localTaxRate < 0) {
alert("Please enter a valid Local Tax Rate.");
return;
}
if (isNaN(postTaxDeductionsPerPeriod) || postTaxDeductionsPerPeriod < 0) {
alert("Please enter valid Post-tax Deductions.");
return;
}
if (isNaN(fedAllowances) || fedAllowances < 0) {
alert("Please enter valid Federal Allowances.");
return;
}
// Annualize amounts
var annualGrossPay = grossPayPerPeriod * payFrequencyMultiplier;
var annualPreTaxDeductions = preTaxDeductionsPerPeriod * payFrequencyMultiplier;
// — FICA Taxes (Social Security & Medicare) —
var annualFicaGross = annualGrossPay; // FICA is generally calculated on gross pay before pre-tax deductions like 401k
var annualSSTax = 0;
if (annualFicaGross addMedThreshold) {
annualMedicareTax += (annualFicaGross – addMedThreshold) * ADD_MED_RATE;
}
// — Federal Income Tax —
var annualTaxableIncomeFed = annualGrossPay – annualPreTaxDeductions;
var standardDeduction = 0;
if (fedFilingStatus === 'single') {
standardDeduction = FED_STD_DEDUCTION_SINGLE;
} else if (fedFilingStatus === 'married') {
standardDeduction = FED_STD_DEDUCTION_MARRIED;
} else if (fedFilingStatus === 'hoh') {
standardDeduction = FED_STD_DEDUCTION_HOH;
}
var allowanceDeduction = fedAllowances * FED_ALLOWANCE_VALUE;
var federalTaxableIncome = annualTaxableIncomeFed – standardDeduction – allowanceDeduction;
if (federalTaxableIncome < 0) {
federalTaxableIncome = 0;
}
var annualFederalTax = 0;
// Simplified 2024 Federal Tax Brackets (Percentage Method for withholding)
// This is a simplified approximation and not the full IRS Pub 15-T tables.
// For accurate withholding, a more complex implementation of Pub 15-T is needed.
if (fedFilingStatus === 'single' || fedFilingStatus === 'hoh') {
if (federalTaxableIncome <= 11600) {
annualFederalTax = federalTaxableIncome * 0.10;
} else if (federalTaxableIncome <= 47150) {
annualFederalTax = 1160 + (federalTaxableIncome – 11600) * 0.12;
} else if (federalTaxableIncome <= 100525) {
annualFederalTax = 5426 + (federalTaxableIncome – 47150) * 0.22;
} else if (federalTaxableIncome <= 191950) {
annualFederalTax = 17168.50 + (federalTaxableIncome – 100525) * 0.24;
} else if (federalTaxableIncome <= 243725) {
annualFederalTax = 39119.50 + (federalTaxableIncome – 191950) * 0.32;
} else if (federalTaxableIncome <= 609350) {
annualFederalTax = 55678.50 + (federalTaxableIncome – 243725) * 0.35;
} else {
annualFederalTax = 183647.25 + (federalTaxableIncome – 609350) * 0.37;
}
} else if (fedFilingStatus === 'married') { // Married Filing Jointly
if (federalTaxableIncome <= 23200) {
annualFederalTax = federalTaxableIncome * 0.10;
} else if (federalTaxableIncome <= 94300) {
annualFederalTax = 2320 + (federalTaxableIncome – 23200) * 0.12;
} else if (federalTaxableIncome <= 201050) {
annualFederalTax = 10852 + (federalTaxableIncome – 94300) * 0.22;
} else if (federalTaxableIncome <= 383900) {
annualFederalTax = 34337 + (federalTaxableIncome – 201050) * 0.24;
} else if (federalTaxableIncome <= 487450) {
annualFederalTax = 78233 + (federalTaxableIncome – 383900) * 0.32;
} else if (federalTaxableIncome <= 731200) {
annualFederalTax = 111353 + (federalTaxableIncome – 487450) * 0.35;
} else {
annualFederalTax = 196665.50 + (federalTaxableIncome – 731200) * 0.37;
}
}
// — PA State Income Tax —
var annualTaxableIncomePA = annualGrossPay – annualPreTaxDeductions; // PA does not allow standard deductions or allowances for state income tax
var annualPAStateTax = annualTaxableIncomePA * PA_STATE_TAX_RATE;
if (annualPAStateTax < 0) annualPAStateTax = 0; // Ensure tax is not negative
// — Local Income Tax (PA) —
var annualTaxableIncomeLocal = annualGrossPay – annualPreTaxDeductions; // Local taxes typically follow state rules for taxable income
var annualLocalTax = annualTaxableIncomeLocal * (localTaxRate / 100);
if (annualLocalTax < 0) annualLocalTax = 0; // Ensure tax is not negative
// — Calculate per-period amounts —
var ssTaxPerPeriod = annualSSTax / payFrequencyMultiplier;
var medicareTaxPerPeriod = annualMedicareTax / payFrequencyMultiplier;
var federalTaxPerPeriod = annualFederalTax / payFrequencyMultiplier;
var paStateTaxPerPeriod = annualPAStateTax / payFrequencyMultiplier;
var localTaxPerPeriod = annualLocalTax / payFrequencyMultiplier;
// — Total Deductions —
var totalDeductionsPerPeriod = federalTaxPerPeriod + paStateTaxPerPeriod + localTaxPerPeriod +
ssTaxPerPeriod + medicareTaxPerPeriod +
preTaxDeductionsPerPeriod + postTaxDeductionsPerPeriod;
// — Net Pay —
var netPayPerPeriod = grossPayPerPeriod – totalDeductionsPerPeriod;
// Display results
document.getElementById('displayGrossPay').innerText = '$' + grossPayPerPeriod.toFixed(2);
document.getElementById('displayFederalTax').innerText = '$' + federalTaxPerPeriod.toFixed(2);
document.getElementById('displayPAStateTax').innerText = '$' + paStateTaxPerPeriod.toFixed(2);
document.getElementById('displayLocalTax').innerText = '$' + localTaxPerPeriod.toFixed(2);
document.getElementById('displaySSTax').innerText = '$' + ssTaxPerPeriod.toFixed(2);
document.getElementById('displayMedicareTax').innerText = '$' + medicareTaxPerPeriod.toFixed(2);
document.getElementById('displayPreTaxDeductions').innerText = '$' + preTaxDeductionsPerPeriod.toFixed(2);
document.getElementById('displayPostTaxDeductions').innerText = '$' + postTaxDeductionsPerPeriod.toFixed(2);
document.getElementById('displayNetPay').innerText = '$' + netPayPerPeriod.toFixed(2);
}
// Run calculation on page load with default values
window.onload = calculatePayroll;
.calculator-container {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
background-color: #f9f9f9;
padding: 25px;
border-radius: 10px;
box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
max-width: 700px;
margin: 30px auto;
border: 1px solid #e0e0e0;
}
.calculator-container h2 {
text-align: center;
color: #333;
margin-bottom: 25px;
font-size: 1.8em;
}
.calculator-inputs .form-group {
margin-bottom: 18px;
display: flex;
flex-direction: column;
}
.calculator-inputs label {
margin-bottom: 8px;
color: #555;
font-weight: bold;
font-size: 0.95em;
}
.calculator-inputs input[type="number"],
.calculator-inputs select {
padding: 10px 12px;
border: 1px solid #ccc;
border-radius: 5px;
font-size: 1em;
width: 100%;
box-sizing: border-box;
transition: border-color 0.3s ease;
}
.calculator-inputs input[type="number"]:focus,
.calculator-inputs select:focus {
border-color: #007bff;
outline: none;
box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
}
button {
display: block;
width: 100%;
padding: 12px;
background-color: #007bff;
color: white;
border: none;
border-radius: 5px;
font-size: 1.1em;
font-weight: bold;
cursor: pointer;
transition: background-color 0.3s ease, transform 0.2s ease;
margin-top: 25px;
}
button:hover {
background-color: #0056b3;
transform: translateY(-1px);
}
button:active {
transform: translateY(0);
}
.calculator-results {
margin-top: 30px;
padding-top: 25px;
border-top: 1px solid #eee;
}
.calculator-results h3 {
color: #333;
margin-bottom: 20px;
text-align: center;
font-size: 1.5em;
}
.calculator-results p {
display: flex;
justify-content: space-between;
padding: 8px 0;
border-bottom: 1px dashed #eee;
font-size: 1em;
color: #444;
}
.calculator-results p:last-of-type {
border-bottom: none;
}
.calculator-results p span {
font-weight: bold;
color: #222;
}
.calculator-results .net-pay {
font-size: 1.2em;
font-weight: bold;
color: #007bff;
border-top: 2px solid #007bff;
padding-top: 15px;
margin-top: 15px;
}
.calculator-results .net-pay span {
color: #007bff;
}
/* Responsive adjustments */
@media (max-width: 600px) {
.calculator-container {
padding: 15px;
margin: 20px auto;
}
.calculator-inputs label {
font-size: 0.9em;
}
.calculator-inputs input[type="number"],
.calculator-inputs select,
button {
font-size: 0.95em;
padding: 10px;
}
.calculator-results h3 {
font-size: 1.3em;
}
.calculator-results p {
font-size: 0.95em;
}
.calculator-results .net-pay {
font-size: 1.1em;
}
}
Understanding Your Pennsylvania Payroll: A Comprehensive Guide
Navigating your paycheck can sometimes feel like deciphering a complex code. For employees in Pennsylvania, understanding how gross pay translates to net pay involves several layers of deductions, including federal, state, and local taxes, as well as mandatory contributions like FICA. This guide breaks down the key components of your PA payroll.
Gross Pay vs. Net Pay
Your Gross Pay is the total amount of money you earn before any deductions are taken out. This is typically your hourly wage multiplied by hours worked, or your annual salary divided by your pay periods. Net Pay, often referred to as "take-home pay," is the amount you receive after all taxes and deductions have been subtracted from your gross pay.
Federal Income Tax
Federal income tax is a progressive tax, meaning higher earners pay a larger percentage of their income in taxes. The amount withheld from your paycheck depends on several factors:
- Gross Wages: Your total earnings.
- Pay Frequency: How often you get paid (weekly, bi-weekly, monthly, etc.).
- Filing Status: Single, Married Filing Jointly, Head of Household, etc.
- Allowances/Dependents: The number of allowances you claim on your W-4 form, which reduces the amount of taxable income.
- Pre-tax Deductions: Certain deductions, like contributions to a 401(k) or health insurance premiums, reduce your taxable income for federal tax purposes.
The IRS provides detailed withholding tables (Publication 15-T) that employers use to calculate the correct amount of federal income tax to withhold. Our calculator uses a simplified percentage method based on these principles to provide an estimate.
FICA Taxes (Social Security and Medicare)
FICA stands for the Federal Insurance Contributions Act, which funds Social Security and Medicare programs. These are mandatory deductions for most employees:
- Social Security: As of 2024, the employee contribution rate is 6.2% of your gross wages, up to an annual wage base limit of $168,600. Once your year-to-date earnings exceed this limit, Social Security tax is no longer withheld for the remainder of the year.
- Medicare: The employee contribution rate is 1.45% of all your gross wages, with no wage base limit. Additionally, an "Additional Medicare Tax" of 0.9% applies to wages exceeding certain thresholds ($200,000 for single filers, $250,000 for married filing jointly, etc.).
Unlike federal income tax, FICA taxes are generally calculated on your gross pay before most pre-tax deductions are applied.
Pennsylvania State Income Tax
Pennsylvania stands out with a flat state income tax rate. As of 2024, the rate is 3.07% of your taxable income. This means everyone pays the same percentage, regardless of their income level. Importantly, Pennsylvania does not allow for personal exemptions or standard deductions against this state income tax, though certain pre-tax deductions (like 401k contributions or health insurance premiums) can reduce your taxable income for state purposes.
Pennsylvania Local Income Tax
One of the unique aspects of payroll in Pennsylvania is the prevalence of local income taxes. These taxes vary significantly by municipality (city, borough, township) and school district. The rates can range from 0% to over 3% and are typically applied to your gross wages or net profits. It's crucial to know your specific municipality and school district to determine your exact local tax rate. Our calculator allows you to input your local tax rate for an accurate estimate.
Pre-tax vs. Post-tax Deductions
- Pre-tax Deductions: These are deductions taken from your gross pay before taxes are calculated. Common examples include contributions to a 401(k) or 403(b) retirement plan, health insurance premiums, and Flexible Spending Account (FSA) contributions. Pre-tax deductions reduce your taxable income, thereby lowering your federal, state, and local income tax liability. However, they generally do not reduce your income for FICA taxes.
- Post-tax Deductions: These deductions are taken from your pay *after* all applicable taxes have been calculated and withheld. Examples include Roth 401(k) contributions, union dues, garnishments, or certain charitable contributions. These deductions do not affect your taxable income.
Using the PA Payroll Calculator
Our Pennsylvania Payroll Calculator provides an estimated breakdown of your paycheck. Simply input your gross pay per period, select your pay frequency, federal filing status, federal allowances, any pre-tax or post-tax deductions, and your specific local income tax rate. The calculator will then estimate your federal, state, local, and FICA taxes, giving you a clear picture of your net pay.
Remember, this calculator provides estimates. For precise figures, always refer to your official pay stubs or consult with a payroll professional or tax advisor.