Federal Income Tax Calculator – Estimate Your Tax Liability
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Income Tax Calculator
Estimated Federal Income Tax Due
$0.00
Taxable Income: $0.00
Tax Rate Bracket: N/A
Tax Within Bracket: $0.00
Tax Based on Previous Brackets: $0.00
Formula Used: Federal income tax is calculated by applying progressive tax rates to different portions (brackets) of your taxable income. The total tax is the sum of the tax calculated for each bracket.
Taxable Income Segments
Tax Due on Segments
Federal Income Tax Breakdown by Brackets
Federal Income Tax Brackets (Illustrative for 2023 – Consult official sources for current year)
| Filing Status |
Bracket 1 (0% to 10%) |
Bracket 2 (12% on $X to $Y) |
Bracket 3 (22% on $Y to $Z) |
Bracket 4 (24% on $Z to $A) |
Bracket 5 (32% on $A to $B) |
Bracket 6 (35% on $B to $C) |
Bracket 7 (37% on $C+) |
Understanding Federal Income Tax Calculation
The calculation of federal income tax is a fundamental aspect of personal finance for individuals in the United States. It determines how much tax you owe to the federal government based on your earnings and specific tax circumstances. This process involves understanding taxable income, tax brackets, and how different income levels are taxed at varying rates. Our comprehensive federal income tax calculator is designed to simplify this complex system, offering a clear estimate of your tax liability.
What is Federal Income Tax?
Federal income tax is a tax imposed by the U.S. federal government on the income of individuals, corporations, and other entities. It is a progressive tax, meaning that higher levels of income are taxed at higher rates. The revenue generated from federal income tax is used to fund various government programs and services, including national defense, social security, and infrastructure projects. Understanding how your federal income tax is calculated is crucial for effective financial planning and ensuring compliance with tax laws.
Who Should Use a Federal Income Tax Calculator?
Anyone who earns income and is subject to U.S. federal income tax should consider using a federal income tax calculator. This includes:
- Employees with W-2 income.
- Self-employed individuals and freelancers with 1099 income.
- Individuals with investment income (dividends, capital gains).
- Anyone seeking to estimate their tax liability before tax season or for budgeting purposes.
- Those who want to understand the impact of deductions and credits on their overall tax burden.
Common Misconceptions about Federal Income Tax
Several common misunderstandings surround federal income tax:
- "My tax rate is X% because that's my bracket." This is incorrect. Your tax bracket represents the rate applied to the *portion* of your income that falls within that bracket, not your entire income.
- "The government takes too much." While tax rates can seem high, it's important to consider the services funded by this revenue and how deductions/credits can reduce your actual tax liability.
- "Tax filing is only for the wealthy." Everyone with income above a certain threshold must file a tax return.
- "Tax calculators are always 100% accurate." Calculators provide estimates. Actual tax liability depends on detailed tax forms, specific circumstances, and potential changes in tax law. For precise figures, always consult official IRS resources or a tax professional.
Federal Income Tax Formula and Mathematical Explanation
The core of the federal income tax calculation lies in the progressive tax bracket system. Here's a step-by-step breakdown:
- Determine Total Income: This includes wages, salaries, tips, investment income, business income, and other sources.
- Calculate Adjusted Gross Income (AGI): Subtract "above-the-line" deductions (like IRA contributions, student loan interest) from total income.
- Calculate Taxable Income: Subtract either the standard deduction or itemized deductions (whichever is greater) from your AGI. This is the amount your tax is actually calculated on.
- Apply Tax Brackets: The taxable income is then divided into portions, each taxed at a specific rate according to the filing status.
The Progressive Tax Bracket System
For a given filing status, there are several income brackets, each with an associated tax rate. The rates increase as income increases. For example, for a "Single" filer, the first portion of taxable income might be taxed at 10%, the next portion at 12%, and so on, up to the highest bracket (currently 37%).
Mathematical Representation:
Let:
- TI = Taxable Income
- F = Filing Status (e.g., Single, Married Filing Jointly)
- Bi = Upper limit of the i-th income bracket for filing status F
- Ri = Tax rate for the i-th income bracket
- Taxi = Tax calculated for the i-th bracket
- Total Tax = Sum of Taxi for all applicable brackets
The calculation for each bracket is typically:
If TI ≤ B1, Tax1 = TI * R1
If B1 < TI ≤ B2, Tax1 = B1 * R1, and Tax2 = (TI – B1) * R2
This continues for all relevant brackets. The total tax is the sum of these calculated amounts.
Variable Explanations
Tax Calculation Variables
| Variable |
Meaning |
Unit |
Typical Range |
| Taxable Income (TI) |
Income remaining after all applicable deductions. |
USD |
$0 to potentially millions |
| Filing Status |
Marital status and dependents affecting bracket sizes. |
Category |
Single, Married Filing Jointly, etc. |
| Tax Bracket Limits (Bi) |
The income thresholds defining each tax rate segment. |
USD |
Varies greatly by status and year (e.g., $0 – $500,000+) |
| Tax Rate (Ri) |
The percentage applied to income within a specific bracket. |
Percentage (%) |
10% to 37% |
| Tax Within Bracket (Taxi) |
Tax amount calculated for income falling into a specific bracket. |
USD |
$0 to potentially hundreds of thousands |
| Total Tax Due |
The sum of taxes from all applicable brackets. |
USD |
$0 to potentially millions |
Practical Examples (Real-World Use Cases)
Example 1: Single Filer
Scenario: Sarah is single and has a taxable income of $70,000 for 2023. Using the 2023 Single filer brackets:
- 10% on income up to $11,000
- 12% on income between $11,001 and $44,725
- 22% on income between $44,726 and $95,375
Calculation:
- Tax on first $11,000: $11,000 * 0.10 = $1,100
- Tax on next $33,725 ($44,725 – $11,000): $33,725 * 0.12 = $4,047
- Tax on remaining $25,275 ($70,000 – $44,725): $25,275 * 0.22 = $5,560.50
Total Estimated Tax: $1,100 + $4,047 + $5,560.50 = $10,707.50
Interpretation: Sarah's estimated federal income tax liability is $10,707.50. Her marginal tax rate (the rate on her last dollar earned) is 22%, but her effective tax rate (total tax divided by total taxable income) is approximately 15.3%. Using our federal income tax calculator would yield this result quickly.
Example 2: Married Filing Jointly
Scenario: John and Jane are married and file jointly. Their combined taxable income is $150,000 for 2023. Using the 2023 Married Filing Jointly brackets:
- 10% on income up to $22,000
- 12% on income between $22,001 and $89,450
- 22% on income between $89,451 and $190,750
Calculation:
- Tax on first $22,000: $22,000 * 0.10 = $2,200
- Tax on next $67,450 ($89,450 – $22,000): $67,450 * 0.12 = $8,094
- Tax on remaining $60,550 ($150,000 – $89,450): $60,550 * 0.22 = $13,321
Total Estimated Tax: $2,200 + $8,094 + $13,321 = $23,615
Interpretation: John and Jane's estimated federal income tax is $23,615. Their marginal tax rate is 22%, and their effective tax rate is approximately 15.7%. This example highlights how the taxable income and filing status significantly impact the final tax bill.
How to Use This Federal Income Tax Calculator
Our federal income tax calculator is designed for ease of use. Follow these simple steps:
- Enter Taxable Income: Input the precise amount of your taxable income. This is the income figure after all eligible deductions have been subtracted from your gross income.
- Select Filing Status: Choose the option that accurately reflects your marital status and tax situation (Single, Married Filing Jointly, etc.).
- Calculate: Click the "Calculate Tax" button.
Reading the Results:
- Estimated Federal Income Tax Due: This is the primary output, showing your projected total federal income tax liability.
- Taxable Income: Confirms the income figure you entered.
- Tax Rate Bracket: Indicates the highest tax bracket your income falls into. Remember, this is your marginal rate, not your effective rate on all income.
- Tax Within Bracket: Shows the amount of tax calculated specifically for the portion of your income that falls within your highest tax bracket.
- Tax Based on Previous Brackets: The sum of taxes calculated for all income falling into lower tax brackets.
- Tax Bracket Table: Provides a reference for the official tax brackets for the current year and filing status.
- Chart: Visually breaks down how your income is taxed across different brackets.
Decision-Making Guidance:
Use the results to budget for your tax payments, understand your tax burden, and identify potential areas where tax planning strategies (like maximizing deductions or retirement contributions) could be beneficial. If your calculated tax seems high, review your deductions and credits. For significant tax planning, consult a qualified tax advisor.
Key Factors That Affect Federal Income Tax Results
Several elements significantly influence the final calculation of your federal income tax:
- Taxable Income Level: This is the most direct factor. Higher taxable income generally means higher tax liability due to the progressive rate structure. Our calculator directly uses this input.
- Filing Status: As demonstrated, your marital status and whether you file jointly or separately drastically alters the tax brackets and, consequently, the tax owed.
- Deductions (Standard vs. Itemized): The choice between the standard deduction and itemizing deductions (like mortgage interest, state/local taxes, charitable donations) directly reduces your taxable income. Choosing the larger deduction lowers your tax bill.
- Tax Credits: Unlike deductions that reduce taxable income, credits directly reduce your tax liability dollar-for-dollar. Examples include the Child Tax Credit, education credits, and energy credits. They can significantly lower the final tax due.
- Tax Advantaged Accounts: Contributions to retirement accounts like 401(k)s and Traditional IRAs often reduce your taxable income for the year, lowering your current tax burden.
- Investment Income Type: Capital gains and qualified dividends are often taxed at lower rates than ordinary income, influencing the overall effective tax rate.
- State and Local Taxes (SALT): While not directly part of federal income tax calculation, the deductibility of state and local taxes (up to a limit) affects your federal taxable income.
- Inflation Adjustments: Tax brackets, standard deductions, and other tax parameters are adjusted annually for inflation, meaning your tax liability can change even if your income and circumstances remain the same.
Frequently Asked Questions (FAQ)
What is the difference between taxable income and gross income?
Gross income is all income earned from all sources. Taxable income is what remains after subtracting eligible deductions (like the standard deduction or itemized deductions) from your Adjusted Gross Income (AGI). The federal income tax is calculated on taxable income.
How do tax credits differ from tax deductions?
Tax deductions reduce your taxable income, meaning you pay tax on a smaller amount. Tax credits directly reduce the amount of tax you owe, dollar for dollar. Credits are generally more valuable than deductions.
Does the calculator account for state income taxes?
No, this calculator specifically estimates only your *federal* income tax liability. State income tax rules and rates vary significantly by state and are not included here.
Can I use this calculator for previous or future tax years?
This calculator uses the most recently available tax bracket data. Tax laws and brackets are subject to change annually. For precise calculations for other years, consult IRS resources or updated calculators.
What is a "progressive tax system"?
A progressive tax system means that the tax rate increases as the taxable amount increases. Higher income earners pay a larger percentage of their income in taxes compared to lower income earners.
What happens if my taxable income falls exactly on a bracket boundary?
If your taxable income falls exactly on a boundary between two tax brackets, the tax calculation correctly applies the lower rate to income up to that boundary and the higher rate to any income exceeding it. The calculator handles these precise calculations.
Should I rely solely on this calculator for my tax filing?
This calculator provides an excellent estimate for planning purposes, but it is not a substitute for professional tax advice or the official IRS tax forms. Your actual tax liability may differ based on complex scenarios, specific investments, or changes in tax law.
How often are the tax brackets updated?
Federal income tax brackets, standard deductions, and other tax parameters are typically adjusted annually for inflation by the IRS. These updates usually take effect for the following tax year.
// Tax bracket data for 2023 (illustrative – always use current official data)
var taxBrackets = {
"single": [
{ limit: 11000, rate: 0.10 },
{ limit: 44725, rate: 0.12 },
{ limit: 95375, rate: 0.22 },
{ limit: 182100, rate: 0.24 },
{ limit: 231250, rate: 0.32 },
{ limit: 578125, rate: 0.35 },
{ limit: Infinity, rate: 0.37 }
],
"married_jointly": [
{ limit: 22000, rate: 0.10 },
{ limit: 89450, rate: 0.12 },
{ limit: 190750, rate: 0.22 },
{ limit: 364200, rate: 0.24 },
{ limit: 462500, rate: 0.32 },
{ limit: 693750, rate: 0.35 },
{ limit: Infinity, rate: 0.37 }
],
"married_separately": [
{ limit: 11000, rate: 0.10 },
{ limit: 44725, rate: 0.12 },
{ limit: 95375, rate: 0.22 },
{ limit: 182100, rate: 0.24 },
{ limit: 231250, rate: 0.32 },
{ limit: 346875, rate: 0.35 },
{ limit: Infinity, rate: 0.37 }
],
"head_of_household": [
{ limit: 15700, rate: 0.10 },
{ limit: 59850, rate: 0.12 },
{ limit: 95350, rate: 0.22 },
{ limit: 182100, rate: 0.24 },
{ limit: 231250, rate: 0.32 },
{ limit: 578125, rate: 0.35 },
{ limit: Infinity, rate: 0.37 }
],
"qualifying_widow": [ // Same as Married Filing Jointly for tax brackets
{ limit: 22000, rate: 0.10 },
{ limit: 89450, rate: 0.12 },
{ limit: 190750, rate: 0.22 },
{ limit: 364200, rate: 0.24 },
{ limit: 462500, rate: 0.32 },
{ limit: 693750, rate: 0.35 },
{ limit: Infinity, rate: 0.37 }
]
};
var chartInstance = null; // Global variable to hold chart instance
function formatCurrency(amount) {
return "$" + amount.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}
function clearError(elementId) {
var errorElement = document.getElementById(elementId);
if (errorElement) {
errorElement.textContent = ";
errorElement.style.display = 'none';
}
}
function displayError(elementId, message) {
var errorElement = document.getElementById(elementId);
if (errorElement) {
errorElement.textContent = message;
errorElement.style.display = 'block';
}
}
function isValidNumber(value) {
return !isNaN(parseFloat(value)) && isFinite(value);
}
function populateBracketTable() {
var tableBody = document.getElementById("taxBracketTableBody");
tableBody.innerHTML = "; // Clear existing rows
var statuses = ["single", "married_jointly", "married_separately", "head_of_household", "qualifying_widow"];
var statusMap = {
"single": "Single",
"married_jointly": "Married Filing Jointly",
"married_separately": "Married Filing Separately",
"head_of_household": "Head of Household",
"qualifying_widow": "Qualifying Widow(er)"
};
var maxBrackets = 0;
statuses.forEach(function(status) {
if (taxBrackets[status].length > maxBrackets) {
maxBrackets = taxBrackets[status].length;
}
});
for (var i = 0; i < maxBrackets; i++) {
var row = tableBody.insertRow();
var cellStatus = row.insertCell();
cellStatus.textContent = (i === 0) ? statusMap[statuses[0]] : ""; // Only show status name for the first row
statuses.forEach(function(status) {
var cell = row.insertCell();
var bracketData = taxBrackets[status];
if (i < bracketData.length) {
var bracket = bracketData[i];
var ratePercent = (bracket.rate * 100).toFixed(1);
var previousLimit = (i === 0) ? 0 : taxBrackets[status][i-1].limit;
if (bracket.limit === Infinity) {
cell.textContent = "$" + previousLimit.toLocaleString() + "+ @ " + ratePercent + "%";
} else {
cell.textContent = "$" + previousLimit.toLocaleString() + " – $" + bracket.limit.toLocaleString() + " @ " + ratePercent + "%";
}
} else {
cell.textContent = "-"; // No bracket at this level for this status
}
});
}
// Add header row dynamically for statuses
var headerRow = tableBody.insertRow(0); // Insert at the beginning
var headerCellStatus = document.createElement('th');
headerCellStatus.textContent = "Filing Status";
headerRow.appendChild(headerCellStatus);
statuses.forEach(function(status) {
var headerCell = document.createElement('th');
headerCell.textContent = statusMap[status];
// Add class for styling if needed
headerRow.appendChild(headerCell);
});
// Apply styles to the dynamically added header
headerRow.style.backgroundColor = 'var(–primary-color)';
headerRow.style.color = 'var(–white)';
headerRow.style.fontWeight = 'bold';
// Correct the column alignment for the header
var headerCells = headerRow.cells;
for (var j = 0; j < headerCells.length; j++) {
headerCells[j].style.textAlign = 'left';
headerCells[j].style.padding = '12px 15px';
}
// Reapply original header styles to the first row which is now the second row
var firstRowCells = tableBody.rows[1].cells; // Accessing the first actual data row
for (var k = 0; k < firstRowCells.length; k++) {
if (k === 0) {
firstRowCells[k].style.fontWeight = 'bold'; // Make status name bold
}
}
}
function calculateTax() {
var taxableIncomeInput = document.getElementById("taxableIncome");
var filingStatusSelect = document.getElementById("filingStatus");
var taxableIncomeValue = taxableIncomeInput.value.trim();
var filingStatus = filingStatusSelect.value;
// Reset errors
clearError("taxableIncomeError");
// Input validation
if (taxableIncomeValue === "") {
displayError("taxableIncomeError", "Please enter your taxable income.");
return;
}
if (!isValidNumber(taxableIncomeValue)) {
displayError("taxableIncomeError", "Invalid number format.");
return;
}
var taxableIncome = parseFloat(taxableIncomeValue);
if (taxableIncome < 0) {
displayError("taxableIncomeError", "Taxable income cannot be negative.");
return;
}
var selectedBrackets = taxBrackets[filingStatus];
if (!selectedBrackets) {
console.error("Invalid filing status selected:", filingStatus);
return;
}
var totalTax = 0;
var taxWithinBracket = 0;
var taxFromLowerBrackets = 0;
var currentBracketIndex = -1;
var taxableIncomeForChart = [];
var taxDueForChart = [];
var cumulativeIncome = 0;
var cumulativeTax = 0;
for (var i = 0; i previousLimit) {
incomeInBracket = Math.min(taxableIncome, bracket.limit) – previousLimit;
var taxInThisBracket = incomeInBracket * rate;
totalTax += taxInThisBracket;
if (bracket.limit === Infinity) { // Last bracket
currentBracketIndex = i;
taxWithinBracket = taxInThisBracket;
taxFromLowerBrackets = totalTax – taxWithinBracket;
}
taxableIncomeForChart.push({
start: previousLimit,
end: Math.min(taxableIncome, bracket.limit),
label: `Bracket ${i + 1} (${(rate * 100).toFixed(0)}%)`
});
taxDueForChart.push(taxInThisBracket);
} else {
// If taxable income is less than the start of this bracket, we stop processing.
// However, we need to ensure previous brackets contributing to the chart are recorded.
// The loop will naturally exit if taxableIncome is not greater than previousLimit.
break;
}
}
// Update results display
document.getElementById("resultTaxableIncome").textContent = formatCurrency(taxableIncome);
document.getElementById("primaryResultValue").textContent = formatCurrency(totalTax);
document.getElementById("taxWithinBracket").textContent = formatCurrency(taxWithinBracket);
document.getElementById("taxFromLowerBrackets").textContent = formatCurrency(taxFromLowerBrackets);
var bracketLabel = "N/A";
if (currentBracketIndex !== -1) {
var bracket = selectedBrackets[currentBracketIndex];
var ratePercent = (bracket.rate * 100).toFixed(0);
bracketLabel = `${ratePercent}% (Bracket ${currentBracketIndex + 1})`;
}
document.getElementById("taxBracket").textContent = bracketLabel;
document.getElementById("results-container").style.display = "block";
document.getElementById("taxChartContainer").style.display = "block";
updateChart(taxableIncomeForChart, taxDueForChart);
}
function resetCalculator() {
document.getElementById("taxableIncome").value = "";
document.getElementById("filingStatus").value = "single";
document.getElementById("results-container").style.display = "none";
document.getElementById("taxChartContainer").style.display = "none";
clearError("taxableIncomeError");
// Clear chart
var ctx = document.getElementById("taxChart").getContext("2d");
ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height);
// Reset chart instance if it exists
if (chartInstance) {
chartInstance.destroy();
chartInstance = null;
}
}
function copyResults() {
var primaryResult = document.getElementById("primaryResultValue").textContent;
var taxableIncome = document.getElementById("resultTaxableIncome").textContent;
var taxBracket = document.getElementById("taxBracket").textContent;
var taxWithinBracket = document.getElementById("taxWithinBracket").textContent;
var taxFromLowerBrackets = document.getElementById("taxFromLowerBrackets").textContent;
var filingStatus = document.getElementById("filingStatus").options[document.getElementById("filingStatus").selectedIndex].text;
var incomeInput = document.getElementById("taxableIncome").value.trim();
var resultsText = "— Federal Income Tax Estimate —\n\n";
resultsText += "Key Assumptions:\n";
resultsText += "- Taxable Income: " + (incomeInput ? formatCurrency(parseFloat(incomeInput)) : "N/A") + "\n";
resultsText += "- Filing Status: " + filingStatus + "\n\n";
resultsText += "Estimated Tax Details:\n";
resultsText += "Estimated Federal Income Tax Due: " + primaryResult + "\n";
resultsText += "Taxable Income: " + taxableIncome + "\n";
resultsText += "Tax Rate Bracket: " + taxBracket + "\n";
resultsText += "Tax Within Bracket: " + taxWithinBracket + "\n";
resultsText += "Tax Based on Previous Brackets: " + taxFromLowerBrackets + "\n";
// Use navigator.clipboard for modern browsers
if (navigator.clipboard && window.isSecureContext) {
navigator.clipboard.writeText(resultsText).then(function() {
alert("Results copied to clipboard!");
}).catch(function(err) {
console.error('Failed to copy: ', err);
fallbackCopyTextToClipboard(resultsText);
});
} else {
fallbackCopyTextToClipboard(resultsText);
}
}
function fallbackCopyTextToClipboard(text) {
var textArea = document.createElement("textarea");
textArea.value = text;
textArea.style.position="fixed";
textArea.style.top = "0";
textArea.style.left = "0";
textArea.style.width = "2em";
textArea.style.height = "2em";
textArea.style.padding="0″;
textArea.style.border="none";
textArea.style.outline="none";
textArea.style.boxShadow="none";
textArea.style.background="transparent";
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand('copy');
var msg = successful ? 'successful' : 'unsuccessful';
alert('Results copied to clipboard (' + msg + ')!');
} catch (err) {
alert('Oops, unable to copy');
}
document.body.removeChild(textArea);
}
function updateChart(taxableIncomeSegments, taxDueSegments) {
var ctx = document.getElementById('taxChart').getContext('2d');
// Destroy previous chart instance if it exists
if (chartInstance) {
chartInstance.destroy();
}
// Prepare data for the chart
var labels = [];
var incomeData = [];
var taxData = [];
var cumulativeIncome = 0;
taxableIncomeSegments.forEach(function(segment, index) {
var startLabel = segment.start.toLocaleString();
var endLabel = segment.end === Infinity ? "∞" : segment.end.toLocaleString();
labels.push(`${segment.label} (${startLabel} – ${endLabel})`);
// For income bars, we need the width of the segment
var segmentWidth = segment.end – segment.start;
incomeData.push(segmentWidth);
// For tax bars, we need the actual tax amount for that segment
taxData.push(taxDueSegments[index]);
cumulativeIncome += segmentWidth;
});
chartInstance = new Chart(ctx, {
type: 'bar',
data: {
labels: labels,
datasets: [{
label: 'Income Segment',
data: incomeData,
backgroundColor: 'rgba(0, 74, 153, 0.6)', // Primary color
borderColor: 'rgba(0, 74, 153, 1)',
borderWidth: 1,
order: 2 // Lower z-index
}, {
label: 'Tax Due on Segment',
data: taxData,
backgroundColor: 'rgba(40, 167, 69, 0.7)', // Success color
borderColor: 'rgba(40, 167, 69, 1)',
borderWidth: 1,
order: 1 // Higher z-index to appear on top
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
x: {
title: {
display: true,
text: 'Tax Bracket Segments'
},
stacked: false // Keep bars separate for clarity
},
y: {
title: {
display: true,
text: 'Amount (USD)'
},
beginAtZero: true,
ticks: {
callback: function(value) {
if (value % 1000 === 0) {
return formatCurrency(value);
}
return null; // Only show labels for thousands
}
}
}
},
plugins: {
tooltip: {
callbacks: {
label: function(context) {
var label = context.dataset.label || ";
if (label) {
label += ': ';
}
if (context.parsed.y !== null) {
label += formatCurrency(context.parsed.y);
}
return label;
}
}
}
}
}
});
}
// Load initial bracket table on page load
document.addEventListener('DOMContentLoaded', function() {
populateBracketTable();
// Add event listener for FAQ toggles
var faqQuestions = document.querySelectorAll('.faq-question');
faqQuestions.forEach(function(question) {
question.addEventListener('click', function() {
var faqItem = this.parentElement;
faqItem.classList.toggle('active');
});
});
// Initial calculation on load if inputs have default values or are pre-filled
if (document.getElementById("taxableIncome").value) {
calculateTax();
}
});