How Can I Calculate How Much House I Can Afford

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How Can I Calculate How Much House I Can Afford?

Understand your home buying power with our detailed affordability calculator and guide.

Home Affordability Calculator

Your total gross income before taxes.
Includes car loans, student loans, credit cards, etc. (excluding current rent/mortgage).
Cash available for your down payment and closing costs.
Excellent (800+) Very Good (740-799) Good (670-739) Fair (580-669) Poor (<580) Higher scores generally lead to better loan terms.
As a percentage (e.g., 1.2 for 1.2%).
Estimated annual cost.
As a percentage (e.g., 0.5 for 0.5%), if applicable. Often required for down payments < 20%.
As a percentage (e.g., 6.5 for 6.5%).
15 Years 30 Years 20 Years 25 Years Common terms are 15 or 30 years.

Your Estimated Maximum Home Price

$0
$0

Max Recommended Monthly Housing Cost

$0

Maximum Loan Amount

0%

Target Debt-to-Income Ratio

How it's calculated: We estimate your maximum affordable monthly housing payment (principal, interest, taxes, insurance, PMI – PITI) based on your income and existing debts, typically aiming for a total debt-to-income ratio (DTI) around 36-43%. From that maximum PITI, we work backward to determine the maximum loan amount and then add your down payment to find the maximum home price.

Monthly Housing Cost Breakdown

Breakdown of estimated monthly costs for the maximum affordable home price.

What is Home Affordability?

Understanding how can I calculate how much house I can afford is a crucial first step for any potential homeowner. Home affordability isn't just about the sticker price of a house; it's a comprehensive financial assessment that determines the maximum home price you can realistically purchase and comfortably manage over the long term. It considers your income, existing debts, savings for a down payment, and the ongoing costs associated with homeownership, such as property taxes, insurance, and potential mortgage insurance.

Who should use this calculator? Anyone considering buying a home, from first-time buyers to those looking to upgrade or downsize. It's particularly useful for individuals who want a realistic financial picture before they start house hunting, helping them set appropriate expectations and avoid overextending their budget. It can also help homeowners understand if they might be able to afford a larger mortgage or a more expensive property.

Common misconceptions about home affordability include believing that lenders' pre-approval amounts are the absolute maximum you should spend (they often represent the upper limit of what they'll lend, not necessarily what's comfortable for your lifestyle) or focusing solely on the mortgage principal and interest without factoring in property taxes, insurance, and other homeownership costs. Many also underestimate the importance of their credit score in determining loan terms and interest rates.

Home Affordability Formula and Mathematical Explanation

Calculating how much house you can afford involves several steps, primarily revolving around your Debt-to-Income (DTI) ratio and the total cost of homeownership (PITI). Lenders typically use two DTI benchmarks: the front-end ratio (housing costs only) and the back-end ratio (all debts). A common guideline is that your total monthly debt payments (including the new mortgage) should not exceed 36% to 43% of your gross monthly income.

Step-by-step derivation:

  1. Calculate Gross Monthly Income (GMI): Annual Income / 12
  2. Estimate Maximum Monthly Housing Payment (PITI): This is the core of affordability. A common rule of thumb is to allocate 28% of GMI for housing costs (Principal, Interest, Taxes, Insurance, PMI). However, a more robust method uses the back-end DTI. Let's assume a target back-end DTI of 36% (this can vary).
    • Maximum Total Monthly Debt = GMI * Target DTI (e.g., 0.36)
    • Maximum PITI = Maximum Total Monthly Debt – Total Monthly Debt Payments (excluding current housing)
  3. Calculate Maximum Loan Amount: This requires working backward from the Maximum PITI. The monthly mortgage payment (P&I) is derived from PITI:
    • Monthly P&I = Maximum PITI – (Monthly Property Tax + Monthly Home Insurance + Monthly PMI)
    • Monthly Property Tax = (Annual Property Tax Rate / 100) * Estimated Home Price / 12
    • Monthly Home Insurance = Annual Home Insurance / 12
    • Monthly PMI = (Annual PMI Rate / 100) * Estimated Home Price / 12
    The mortgage payment formula (M) is: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1] Where: P = Principal loan amount i = Monthly interest rate (Annual Rate / 12 / 100) n = Total number of payments (Loan Term in Years * 12) We rearrange this to solve for P (Principal Loan Amount): P = M * [ (1 + i)^n – 1] / [ i(1 + i)^n ] This gives us the maximum loan amount based on the calculated Monthly P&I.
  4. Calculate Maximum Home Price: Maximum Home Price = Maximum Loan Amount + Available Down Payment

Variables Used in Calculation

Variable Meaning Unit Typical Range / Notes
Annual Household Income Total gross income from all sources before taxes. Currency (e.g., USD) e.g., $50,000 – $500,000+
Total Monthly Debt Payments Sum of minimum monthly payments for all non-housing debts (credit cards, auto loans, student loans, personal loans). Currency (e.g., USD) e.g., $0 – $5,000+
Available Down Payment Cash readily available for the down payment and closing costs. Currency (e.g., USD) e.g., $0 – $200,000+
Estimated Credit Score A measure of creditworthiness. Affects interest rates. Score (e.g., 300-850) e.g., 500 – 850
Annual Property Tax Rate The yearly property tax as a percentage of the home's value. Percentage (%) e.g., 0.5% – 3.0%
Annual Homeowners Insurance Estimated yearly cost to insure the property. Currency (e.g., USD) e.g., $800 – $3,000+
Annual PMI/MIP Rate Private Mortgage Insurance or Mortgage Insurance Premium rate, often required for low down payments. Percentage (%) e.g., 0.25% – 1.5%
Estimated Mortgage Interest Rate The annual interest rate offered on the mortgage loan. Percentage (%) e.g., 3.0% – 10.0%+
Mortgage Loan Term The duration of the mortgage loan in years. Years Commonly 15 or 30 years.
Gross Monthly Income (GMI) Monthly income before taxes. Currency (e.g., USD) Calculated: Annual Income / 12
Maximum PITI The maximum affordable total monthly housing payment (Principal, Interest, Taxes, Insurance, PMI). Currency (e.g., USD) Calculated based on DTI targets.
Maximum Loan Amount The highest principal amount you can borrow based on PITI and loan terms. Currency (e.g., USD) Calculated using mortgage payment formula.
Maximum Home Price The estimated highest price you can afford. Currency (e.g., USD) Calculated: Max Loan Amount + Down Payment
Debt-to-Income Ratio (DTI) Percentage of gross monthly income used for debt payments. Percentage (%) Target: ~36-43% (back-end)

Practical Examples (Real-World Use Cases)

Example 1: Young Professional Couple

Scenario: Alex and Ben are a couple earning a combined annual income of $120,000. They have $30,000 saved for a down payment and closing costs. Their only significant monthly debt is a $400 car payment and $200 in student loans. They have a good credit score (750) and estimate property taxes at 1.1% annually, home insurance at $1,800/year, and PMI at 0.6% annually since their down payment is less than 20% of the expected home price. They are considering a 30-year mortgage at 6.5% interest.

Inputs:

  • Annual Income: $120,000
  • Monthly Debt: $600 ($400 car + $200 student loans)
  • Down Payment: $30,000
  • Credit Score: 750 (Very Good)
  • Property Tax Rate: 1.1%
  • Home Insurance: $1,800
  • PMI Rate: 0.6%
  • Interest Rate: 6.5%
  • Loan Term: 30 Years

Calculator Output (Illustrative):

  • Max Recommended Monthly Housing Cost: ~$2,800
  • Max Loan Amount: ~$350,000
  • Maximum Home Price: ~$380,000
  • Target Debt-to-Income Ratio: ~36%

Financial Interpretation: Alex and Ben can likely afford a home priced around $380,000. Their maximum monthly housing payment (PITI) would be approximately $2,800, which fits within a 36% DTI ratio when combined with their existing $600 in debt payments. This budget allows them to explore homes in the $350,000-$380,000 range, depending on the exact property taxes and insurance costs.

Example 2: Established Family

Scenario: Sarah and Mark have a stable household income of $180,000 annually. They have accumulated $80,000 for a down payment. Their existing monthly debts include a $600 mortgage on a rental property, a $300 car payment, and $500 in credit card payments, totaling $1,400 per month. Their credit scores are excellent (780). They estimate property taxes at 1.5% annually, home insurance at $2,200/year, and no PMI needed as they plan a substantial down payment. They are looking at a 15-year mortgage at 6.0% interest.

Inputs:

  • Annual Income: $180,000
  • Monthly Debt: $1,400 ($600 rental mortgage + $300 car + $500 credit cards)
  • Down Payment: $80,000
  • Credit Score: 780 (Excellent)
  • Property Tax Rate: 1.5%
  • Home Insurance: $2,200
  • PMI Rate: 0%
  • Interest Rate: 6.0%
  • Loan Term: 15 Years

Calculator Output (Illustrative):

  • Max Recommended Monthly Housing Cost: ~$3,500
  • Max Loan Amount: ~$400,000
  • Maximum Home Price: ~$480,000
  • Target Debt-to-Income Ratio: ~43%

Financial Interpretation: With their strong income, significant down payment, and excellent credit, Sarah and Mark can afford a higher-priced home, potentially up to $480,000. Their maximum monthly housing payment could reach around $3,500, pushing their total DTI towards the higher end of acceptable lender limits (43%). The shorter 15-year term means higher monthly payments but less interest paid over time.

How to Use This Home Affordability Calculator

Using the how can I calculate how much house I can afford calculator is straightforward. Follow these steps:

  1. Gather Your Financial Information: Collect details about your annual household income, all existing monthly debt payments (excluding current rent/mortgage), your available cash for a down payment and closing costs, and your estimated credit score.
  2. Input Property-Specific Costs: Estimate the annual property tax rate for the area you're interested in, the annual cost of homeowners insurance, and the potential annual rate for Private Mortgage Insurance (PMI) if your down payment will be less than 20%.
  3. Enter Loan Details: Input the current estimated mortgage interest rate and the desired loan term (e.g., 15 or 30 years).
  4. Click "Calculate Affordability": The calculator will process your inputs.

How to read results:

  • Maximum Home Price: This is the estimated highest price you can afford, considering all factors.
  • Maximum Recommended Monthly Housing Cost (PITI): This is the total monthly cost, including principal, interest, property taxes, homeowners insurance, and PMI (if applicable). Aim to keep this within your comfortable budget.
  • Maximum Loan Amount: The principal amount you could borrow based on the calculated PITI and loan terms.
  • Target Debt-to-Income Ratio: Shows the percentage of your gross monthly income that would go towards all debt payments (including the estimated new mortgage). Lenders often prefer this to be below 43%.

Decision-making guidance: Use these figures as a guideline. It's wise to aim for a home price slightly below the maximum calculated amount to provide a financial cushion for unexpected expenses, home maintenance, and lifestyle choices. Always consult with a mortgage professional for a personalized assessment and pre-approval.

Key Factors That Affect Home Affordability

Several critical factors influence how much house you can afford. Understanding these can help you optimize your financial position:

  • Income Stability and Amount: Higher and more stable income generally increases borrowing power. Lenders scrutinize income sources, especially for self-employed individuals. Consistent income is key to long-term affordability.
  • Existing Debt Load: High levels of existing debt (credit cards, car loans, student loans) significantly reduce the amount you can borrow for a mortgage, as they increase your DTI ratio. Paying down debt before applying for a mortgage is crucial.
  • Down Payment Size: A larger down payment reduces the loan amount needed, lowers your loan-to-value (LTV) ratio, potentially eliminates PMI, and can lead to better interest rates. It also reduces the overall financial risk.
  • Credit Score: A higher credit score (typically 740+) unlocks access to the best mortgage interest rates, significantly lowering your monthly payments and the total interest paid over the life of the loan. Even a small difference in interest rate can impact affordability by tens of thousands of dollars.
  • Interest Rates: Mortgage interest rates have a direct and substantial impact. Higher rates mean higher monthly payments for the same loan amount, thus reducing the maximum loan you can qualify for. Fluctuations in market rates can change affordability quickly.
  • Property Taxes and Homeowners Insurance: These are ongoing costs that are part of your monthly housing payment (PITI). Areas with high property taxes or insurance costs will reduce the amount you can spend on the principal and interest portion of the mortgage, lowering the affordable home price.
  • PMI/MIP: If your down payment is less than 20%, Private Mortgage Insurance (PMI) or FHA's Mortgage Insurance Premium (MIP) will be added to your monthly payment, increasing your total housing cost and reducing affordability.
  • Economic Conditions & Inflation: Broader economic factors like inflation can affect purchasing power and interest rate trends. Lenders also consider the overall economic outlook when assessing risk.

Frequently Asked Questions (FAQ)

Q1: What is the 'rule of thumb' for home affordability?

A: A common guideline is the 28/36 rule: your total housing costs (PITI) shouldn't exceed 28% of your gross monthly income, and your total debt (including PITI) shouldn't exceed 36%. However, many lenders now allow higher DTIs (up to 43% or more) depending on other factors.

Q2: How much down payment do I need?

A: While 20% down payment is often cited to avoid PMI, many loan programs allow for much lower down payments (e.g., FHA loans at 3.5%, conventional loans at 3-5%). However, a larger down payment reduces your loan amount and monthly payments.

Q3: Does my credit score really matter that much?

A: Yes, significantly. A higher credit score qualifies you for lower interest rates, which can save you tens or even hundreds of thousands of dollars in interest over the life of a 30-year mortgage. It also impacts your ability to get approved.

Q4: What are closing costs?

A: Closing costs are fees paid at the end of a real estate transaction. They typically range from 2% to 5% of the loan amount and can include appraisal fees, title insurance, lender fees, attorney fees, and pre-paid items like property taxes and homeowners insurance.

Q5: Can I include my current rent in my monthly debt?

A: No, the calculator and lenders typically exclude your current rent or mortgage payment when calculating your *new* maximum housing payment. They focus on your *other* existing debts (car loans, credit cards, etc.) to determine how much room you have for a new mortgage payment.

Q6: What if my income is variable (e.g., self-employed)?

A: Lenders will typically average your income over the past 2-3 years and may require additional documentation. Affordability calculations become more conservative. It's best to speak directly with a mortgage broker or lender.

Q7: How do property taxes affect affordability?

A: Property taxes are a significant part of your monthly housing payment (PITI). Higher property taxes in a given area mean less of your maximum monthly housing budget is available for the principal and interest on the loan, thus lowering the maximum home price you can afford.

Q8: Is the calculator's result a guarantee?

A: No, this calculator provides an estimate based on common financial guidelines and your inputs. Actual loan approval amounts and terms depend on the lender's specific underwriting criteria, appraisal values, and a full review of your financial situation.

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Calculate Gross Monthly Income (GMI) var gmi = annualIncome / 12; // 2. Determine Target DTI and Max Total Monthly Debt // Adjust DTI based on credit score (simplified) var targetDtiRatio = 0.36; // Base target DTI if (creditScore >= 740) { targetDtiRatio = 0.40; // Slightly higher for good credit } if (creditScore >= 800) { targetDtiRatio = 0.43; // Higher for excellent credit } if (creditScore < 670) { targetDtiRatio = 0.33; // Lower for fair credit } var maxTotalMonthlyDebt = gmi * targetDtiRatio; // 3. Calculate Max PITI (Principal, Interest, Taxes, Insurance, PMI) var maxPiti = maxTotalMonthlyDebt – monthlyDebt; // Ensure maxPiti is not negative if (maxPiti < 0) maxPiti = 0; // 4. Calculate Monthly Taxes, Insurance, PMI components // We need an estimated home price to calculate these accurately. // This requires an iterative approach or a simplified assumption. // Let's use an iterative approach to find the home price. var estimatedHomePrice = downPayment + 100000; // Initial guess var maxLoanAmount = 0; var calculatedPiti = 0; var tolerance = 0.5; // Tolerance for iteration var maxIterations = 100; var iteration = 0; do { var monthlyPropertyTax = (propertyTaxRate / 100) * estimatedHomePrice / 12; var monthlyHomeInsurance = homeInsurance / 12; var monthlyPmi = (pmiRate / 100) * estimatedHomePrice / 12; // Ensure components are not negative monthlyPropertyTax = Math.max(0, monthlyPropertyTax); monthlyHomeInsurance = Math.max(0, monthlyHomeInsurance); monthlyPmi = Math.max(0, monthlyPmi); var monthlyPrincipalInterest = maxPiti – monthlyPropertyTax – monthlyHomeInsurance – monthlyPmi; // Ensure P&I is not negative if (monthlyPrincipalInterest < 0) { estimatedHomePrice -= 1000; // Reduce price guess if PITI exceeds max continue; } // Calculate max loan amount based on this P&I maxLoanAmount = calculateMortgagePayment(estimatedHomePrice – downPayment, interestRate, loanTerm); // Recalculate PITI based on the calculated maxLoanAmount var actualLoanAmount = estimatedHomePrice – downPayment; if (actualLoanAmount 0) { calculatedMonthlyPITI += calculateMortgagePayment(actualLoanAmount, interestRate, loanTerm); } calculatedPiti = calculatedMonthlyPITI; // Adjust estimatedHomePrice for next iteration if (calculatedPiti > maxPiti) { estimatedHomePrice -= (calculatedPiti – maxPiti) / ( (propertyTaxRate/100/12) + (homeInsurance/12/estimatedHomePrice) + (pmiRate/100/12) + (interestRate/12/100) ); // Crude adjustment if (estimatedHomePrice tolerance && iteration < maxIterations); // Final calculation based on the converged estimatedHomePrice var finalMonthlyPropertyTax = (propertyTaxRate / 100) * estimatedHomePrice / 12; var finalMonthlyHomeInsurance = homeInsurance / 12; var finalMonthlyPmi = (pmiRate / 100) * estimatedHomePrice / 12; var finalLoanAmount = estimatedHomePrice – downPayment; if (finalLoanAmount 0) { finalMonthlyPrincipalInterest = calculateMortgagePayment(finalLoanAmount, interestRate, loanTerm); } var finalMaxPiti = finalMonthlyPrincipalInterest + finalMonthlyPropertyTax + finalMonthlyHomeInsurance + finalMonthlyPmi; var finalMaxLoanAmount = finalLoanAmount; // This is the loan amount corresponding to the final price // Recalculate DTI for display var finalTotalMonthlyDebt = monthlyDebt + finalMaxPiti; var finalDtiRatio = (finalTotalMonthlyDebt / (annualIncome / 12)) * 100; if (isNaN(finalDtiRatio) || !isFinite(finalDtiRatio)) finalDtiRatio = 0; // Format results getElement('maxHomePrice').textContent = formatCurrency(estimatedHomePrice); getElement('maxMonthlyPayment').textContent = formatCurrency(finalMaxPiti); getElement('maxLoanAmount').textContent = formatCurrency(finalMaxLoanAmount); getElement('debtToIncomeRatio').textContent = finalDtiRatio.toFixed(1) + '%'; getElement('resultsContainer').style.display = 'block'; // Update Chart updateChart(finalMaxPiti, finalMonthlyPrincipalInterest, finalMonthlyPropertyTax, finalMonthlyHomeInsurance, finalMonthlyPmi); } function formatCurrency(amount) { if (isNaN(amount) || !isFinite(amount)) return "$0"; return "$" + amount.toFixed(0).replace(/\B(?=(\d{3})+(?!\d))/g, ","); } function resetCalculator() { getElement('annualIncome').value = '80000'; getElement('monthlyDebt').value = '1200'; getElement('downPayment').value = '40000'; getElement('creditScore').value = '740'; // Default to Very Good getElement('propertyTaxRate').value = '1.2'; getElement('homeInsurance').value = '1500'; getElement('pmiRate').value = '0.5'; getElement('interestRate').value = '6.5'; getElement('loanTerm').value = '30'; // Clear errors getElement('annualIncomeError').textContent = "; getElement('monthlyDebtError').textContent = "; getElement('downPaymentError').textContent = "; getElement('propertyTaxRateError').textContent = "; getElement('homeInsuranceError').textContent = "; getElement('pmiRateError').textContent = "; getElement('interestRateError').textContent = "; getElement('resultsContainer').style.display = 'none'; // Optionally clear chart or reset to default state if (window.housingCostChartInstance) { window.housingCostChartInstance.destroy(); window.housingCostChartInstance = null; } } function copyResults() { var maxHomePrice = getElement('maxHomePrice').textContent; var maxMonthlyPayment = getElement('maxMonthlyPayment').textContent; var maxLoanAmount = getElement('maxLoanAmount').textContent; var debtToIncomeRatio = getElement('debtToIncomeRatio').textContent; var annualIncome = getElement('annualIncome').value; var monthlyDebt = getElement('monthlyDebt').value; var downPayment = getElement('downPayment').value; var creditScore = getElement('creditScore').options[getElement('creditScore').selectedIndex].text; var propertyTaxRate = getElement('propertyTaxRate').value; var homeInsurance = getElement('homeInsurance').value; var pmiRate = getElement('pmiRate').value; var interestRate = getElement('interestRate').value; var loanTerm = getElement('loanTerm').options[getElement('loanTerm').selectedIndex].text; var textToCopy = `— Home Affordability Results —\n\n` + `Maximum Home Price: ${maxHomePrice}\n` + `Maximum Recommended Monthly Housing Cost (PITI): ${maxMonthlyPayment}\n` + `Maximum Loan Amount: ${maxLoanAmount}\n` + `Target Debt-to-Income Ratio: ${debtToIncomeRatio}\n\n` + `— Key Assumptions —\n` + `Annual Income: $${annualIncome}\n` + `Total Monthly Debt Payments: $${monthlyDebt}\n` + `Available Down Payment: $${downPayment}\n` + `Estimated Credit Score: ${creditScore}\n` + `Annual Property Tax Rate: ${propertyTaxRate}%\n` + `Annual Homeowners Insurance: $${homeInsurance}\n` + `Annual PMI Rate: ${pmiRate}%\n` + `Estimated Mortgage Interest Rate: ${interestRate}%\n` + `Mortgage Loan Term: ${loanTerm}`; navigator.clipboard.writeText(textToCopy).then(function() { // Optional: Show a confirmation message var originalButtonText = getElement('copyResultsButton') ? getElement('copyResultsButton').textContent : "Copy Results"; if (getElement('copyResultsButton')) getElement('copyResultsButton').textContent = 'Copied!'; setTimeout(function() { if (getElement('copyResultsButton')) getElement('copyResultsButton').textContent = originalButtonText; }, 2000); }).catch(function(err) { console.error('Failed to copy text: ', err); alert('Failed to copy results. Please copy manually.'); }); } // Charting Logic var housingCostChartInstance = null; function updateChart(maxPiti, principalInterest, taxes, insurance, pmi) { var ctx = getElement('housingCostChart').getContext('2d'); // Destroy previous chart instance if it exists if (housingCostChartInstance) { housingCostChartInstance.destroy(); } // Calculate percentages for stacking var totalHousingCost = principalInterest + taxes + insurance + pmi; var piPercent = (principalInterest / totalHousingCost) * 100; var taxPercent = (taxes / totalHousingCost) * 100; var insPercent = (insurance / totalHousingCost) * 100; var pmiPercent = (pmi / totalHousingCost) * 100; // Handle cases where totalHousingCost might be zero or very small if (isNaN(piPercent) || !isFinite(piPercent)) piPercent = 0; if (isNaN(taxPercent) || !isFinite(taxPercent)) taxPercent = 0; if (isNaN(insPercent) || !isFinite(insPercent)) insPercent = 0; if (isNaN(pmiPercent) || !isFinite(pmiPercent)) pmiPercent = 0; // Adjust percentages if they don't sum to 100 due to rounding or zero values var sumPercents = piPercent + taxPercent + insPercent + pmiPercent; if (sumPercents > 0 && Math.abs(sumPercents – 100) > 0.1) { var scaleFactor = 100 / sumPercents; piPercent *= scaleFactor; taxPercent *= scaleFactor; insPercent *= scaleFactor; pmiPercent *= scaleFactor; } housingCostChartInstance = new Chart(ctx, { type: 'bar', data: { labels: ['Monthly Housing Cost Breakdown'], datasets: [{ label: 'Principal & Interest', data: [piPercent], backgroundColor: 'rgba(0, 74, 153, 0.7)', // Primary color borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1 }, { label: 'Property Taxes', data: [taxPercent], backgroundColor: 'rgba(40, 167, 69, 0.7)', // Success color borderColor: 'rgba(40, 167, 69, 1)', borderWidth: 1 }, { label: 'Home Insurance', data: [insPercent], backgroundColor: 'rgba(255, 193, 7, 0.7)', // Warning color borderColor: 'rgba(255, 193, 7, 1)', borderWidth: 1 }, { label: 'PMI/MIP', data: [pmiPercent], backgroundColor: 'rgba(108, 117, 125, 0.7)', // Secondary color borderColor: 'rgba(108, 117, 125, 1)', borderWidth: 1 }] }, options: { indexAxis: 'y', // Horizontal bar chart responsive: true, maintainAspectRatio: false, scales: { x: { stacked: true, title: { display: true, text: 'Percentage of Max Monthly Housing Cost' }, ticks: { callback: function(value) { return value + '%'; } } }, y: { stacked: true } }, plugins: { legend: { position: 'bottom', }, tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.parsed.x !== null) { // Find the corresponding dollar amount var dollarAmount = 0; if (context.dataset.label === 'Principal & Interest') dollarAmount = principalInterest; else if (context.dataset.label === 'Property Taxes') dollarAmount = taxes; else if (context.dataset.label === 'Home Insurance') dollarAmount = insurance; else if (context.dataset.label === 'PMI/MIP') dollarAmount = pmi; label += formatCurrency(dollarAmount) + ' ($' + context.parsed.x.toFixed(1) + '%)'; } return label; } } } } } }); } // Initial calculation on load if defaults are set document.addEventListener('DOMContentLoaded', function() { // Set default values and trigger calculation resetCalculator(); // Sets defaults calculateAffordability(); // Calculates based on defaults // Add event listeners for real-time updates (optional, but good UX) var inputs = document.querySelectorAll('.loan-calc-container input, .loan-calc-container select'); inputs.forEach(function(input) { input.addEventListener('input', calculateAffordability); input.addEventListener('change', calculateAffordability); // For select elements }); }); // Add Chart.js library dynamically if not present if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js@3.7.0/dist/chart.min.js'; script.onload = function() { console.log('Chart.js loaded.'); // Recalculate after chart library is loaded if needed if (getElement('resultsContainer').style.display === 'block') { calculateAffordability(); } }; document.head.appendChild(script); }

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