.calculator-container {
max-width: 800px;
margin: 0 auto;
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
padding: 20px;
background: #f9f9f9;
border-radius: 8px;
box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}
.calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
.calc-grid {
grid-template-columns: 1fr;
}
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #333;
}
.input-group input, .input-group select {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.btn-calc {
background-color: #2c3e50;
color: white;
border: none;
padding: 15px 30px;
font-size: 18px;
font-weight: bold;
border-radius: 4px;
cursor: pointer;
width: 100%;
margin-top: 10px;
transition: background 0.3s;
}
.btn-calc:hover {
background-color: #34495e;
}
#affordabilityResult {
margin-top: 25px;
padding: 20px;
background: #fff;
border: 1px solid #e1e1e1;
border-radius: 6px;
display: none;
}
.result-header {
text-align: center;
font-size: 1.2rem;
color: #7f8c8d;
margin-bottom: 5px;
}
.result-value {
text-align: center;
font-size: 2.5rem;
font-weight: 800;
color: #27ae60;
margin-bottom: 20px;
}
.breakdown-row {
display: flex;
justify-content: space-between;
padding: 8px 0;
border-bottom: 1px solid #eee;
}
.breakdown-row:last-child {
border-bottom: none;
}
.seo-content {
margin-top: 40px;
line-height: 1.6;
color: #444;
}
.seo-content h2 {
color: #2c3e50;
margin-top: 30px;
}
.seo-content h3 {
color: #34495e;
margin-top: 20px;
}
.error-msg {
color: #c0392b;
text-align: center;
margin-top: 10px;
display: none;
}
function calculateAffordability() {
// Get inputs
var income = parseFloat(document.getElementById('ma_income').value);
var debts = parseFloat(document.getElementById('ma_debts').value) || 0;
var down = parseFloat(document.getElementById('ma_down').value) || 0;
var rate = parseFloat(document.getElementById('ma_rate').value);
var term = parseInt(document.getElementById('ma_term').value);
var ptax = parseFloat(document.getElementById('ma_ptax').value) || 0;
var ins = parseFloat(document.getElementById('ma_ins').value) || 0;
var dtiLimit = parseFloat(document.getElementById('ma_dti').value);
// Error handling
if (isNaN(income) || isNaN(rate) || income <= 0) {
document.getElementById('calcError').style.display = 'block';
document.getElementById('affordabilityResult').style.display = 'none';
return;
} else {
document.getElementById('calcError').style.display = 'none';
}
// Calculations
var monthlyIncome = income / 12;
// Back-End Ratio Calculation: (Monthly Income * DTI) – Debts
var maxTotalPayment = (monthlyIncome * dtiLimit) – debts;
// Front-End Ratio Check (Standard 28% rule, usually less strict than back-end but good to check)
// We stick to the user selected DTI mainly, but cap if result is negative
if (maxTotalPayment < 0) maxTotalPayment = 0;
// Calculate Monthly Taxes and Insurance
var monthlyTax = ptax / 12;
var monthlyIns = ins / 12;
var monthlyEscrow = monthlyTax + monthlyIns;
// Available for Principal & Interest
var availableForPI = maxTotalPayment – monthlyEscrow;
if (availableForPI < 0) availableForPI = 0;
// Calculate Max Loan Amount based on P&I payment
// Formula: Loan = P * (1 – (1+r)^-n) / r
var r = rate / 100 / 12;
var n = term * 12;
var maxLoan = 0;
if (r === 0) {
maxLoan = availableForPI * n;
} else {
maxLoan = availableForPI * (1 – Math.pow(1 + r, -n)) / r;
}
// Max Home Price
var maxHomePrice = maxLoan + down;
// Formatting currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
maximumFractionDigits: 0
});
// Update UI
document.getElementById('res_maxPrice').innerHTML = formatter.format(maxHomePrice);
document.getElementById('res_maxMonthly').innerHTML = formatter.format(maxTotalPayment);
document.getElementById('res_pi').innerHTML = formatter.format(availableForPI);
document.getElementById('res_ti').innerHTML = formatter.format(monthlyEscrow);
document.getElementById('res_loanAmount').innerHTML = formatter.format(maxLoan);
document.getElementById('res_down').innerHTML = formatter.format(down);
document.getElementById('affordabilityResult').style.display = 'block';
}
How Much House Can I Afford?
30 Years
20 Years
15 Years
10 Years
Conservative (36% Back-End)
Standard (43% Back-End)
Aggressive (50% Back-End)
Please enter valid numeric values for Income and Interest Rate.
Estimated Maximum Home Price
$0
Max Monthly Payment (PITI):
$0
Principal & Interest:
$0
Taxes & Insurance:
$0
Loan Amount:
$0
Down Payment:
$0
Understanding Your Home Affordability
Determining "How much house can I afford?" is the critical first step in the home buying journey. This mortgage affordability calculator provides a realistic estimate based on your gross annual income, monthly debts, and the current financing environment. Unlike simple payment calculators, this tool considers your Debt-to-Income (DTI) ratio, which is the primary metric lenders use to approve mortgages.
Key Factors That Influence Affordability
Several variables impact your purchasing power beyond just your salary:
- Debt-to-Income Ratio (DTI): This is the percentage of your monthly gross income that goes toward paying debts. Most lenders prefer a "back-end" ratio (total house payment + other debts) of no more than 43%, though some government loans allow up to 50%.
- Down Payment: A larger down payment increases your maximum home price dollar-for-dollar without increasing your monthly payment. It may also remove the need for Private Mortgage Insurance (PMI).
- Interest Rates: Even a small 1% increase in interest rates can significantly reduce your buying power by increasing the cost of borrowing.
- Property Taxes & Insurance: These ongoing costs effectively reduce the portion of your monthly payment available for the loan principal, thereby lowering the loan amount you can qualify for in high-tax areas.
How We Calculate Your Maximum Home Price
The calculation follows the underwriting standards used by major banks:
- We calculate your monthly gross income.
- We determine your maximum allowable monthly debt usage based on the selected DTI limit (e.g., 43%).
- We subtract your existing monthly obligations (car loans, student loans, credit cards) to find the maximum allowance for a housing payment.
- We subtract estimated property taxes and homeowners insurance.
- The remaining amount is the maximum "Principal and Interest" payment you can afford. Using the interest rate and loan term, we reverse-engineer the maximum loan amount and add your down payment to find the total home price.
Improving Your Home Buying Power
If the result is lower than current home prices in your area, consider paying down high-payment monthly debts (like credit cards) to improve your DTI ratio. Alternatively, saving for a larger down payment or improving your credit score to qualify for a lower interest rate can drastically increase your affordability range.