Calculate your estimated monthly mortgage payment for a home in California, including principal, interest, property taxes, and homeowners insurance.
15 Years
20 Years
30 Years
Your Estimated Monthly Mortgage Payment:
$0.00
Understanding Your California Mortgage Payment
When purchasing a home in California, understanding all components of your monthly mortgage payment is crucial. While many focus on the principal and interest, there are other significant costs, especially in a high-cost-of-living state like California. This calculator helps you estimate your total PITI payment, which includes:
Principal: The amount borrowed to buy the home.
Interest: The cost of borrowing money, based on your interest rate.
Property Taxes: Taxes levied by local governments, often based on a percentage of your home's assessed value. California's property tax rate is typically around 1% of the assessed value (based on Proposition 13), plus any local bonds or assessments, which can vary significantly by county and city.
Homeowners Insurance: Covers damages to your home and liability. Rates vary based on coverage, location, and insurer.
How the Calculation Works
The calculator uses the following formulas to estimate your monthly mortgage payment:
Loan Amount:
Loan Amount = Home Price - Down Payment
Monthly Principal & Interest (P&I): This is calculated using the standard mortgage payment formula:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]</code
Where:
M = Your total monthly mortgage payment (Principal & Interest)
P = The principal loan amount
i = Your monthly interest rate (Annual Interest Rate / 12)
n = The total number of payments over the loan's lifetime (Loan Term in Years * 12)
California's real estate market has unique characteristics. Property taxes, while capped by Proposition 13 for existing homeowners, can be a substantial part of the payment for new buyers, especially if the home was recently sold. Additionally, homeowners insurance costs can vary significantly due to wildfire risk in many areas, earthquake risk (though typically covered by a separate policy), and general insurance market conditions. It's always recommended to get personalized quotes for insurance and consult with a local mortgage professional for the most accurate figures.
This calculator provides an estimate to help you budget for your potential homeownership costs in California.
function calculateMortgage() {
var homePrice = parseFloat(document.getElementById("homePrice").value);
var downPayment = parseFloat(document.getElementById("downPayment").value);
var loanTerm = parseInt(document.getElementById("loanTerm").value);
var interestRate = parseFloat(document.getElementById("interestRate").value);
var annualPropTaxRate = parseFloat(document.getElementById("annualPropTax").value);
var annualHomeIns = parseFloat(document.getElementById("annualHomeIns").value);
var resultDiv = document.getElementById("result");
var monthlyPaymentDisplay = document.getElementById("monthlyPayment");
// Input validation
if (isNaN(homePrice) || homePrice <= 0 ||
isNaN(downPayment) || downPayment < 0 ||
isNaN(loanTerm) || loanTerm <= 0 ||
isNaN(interestRate) || interestRate < 0 ||
isNaN(annualPropTaxRate) || annualPropTaxRate < 0 ||
isNaN(annualHomeIns) || annualHomeIns homePrice) {
alert("Down payment cannot be greater than the home price.");
resultDiv.style.display = 'none';
return;
}
var loanAmount = homePrice - downPayment;
var monthlyInterestRate = (interestRate / 100) / 12;
var numberOfPayments = loanTerm * 12;
var monthlyPI = 0;
if (monthlyInterestRate > 0) {
monthlyPI = loanAmount * (monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numberOfPayments)) / (Math.pow(1 + monthlyInterestRate, numberOfPayments) - 1);
} else {
// Handle 0 interest rate case (though unlikely for mortgages)
monthlyPI = loanAmount / numberOfPayments;
}
var monthlyPropTax = (homePrice * (annualPropTaxRate / 100)) / 12;
var monthlyHomeIns = annualHomeIns / 12;
var totalMonthlyPayment = monthlyPI + monthlyPropTax + monthlyHomeIns;
if (isNaN(totalMonthlyPayment) || totalMonthlyPayment < 0) {
alert("Calculation resulted in an invalid number. Please check your inputs.");
resultDiv.style.display = 'none';
return;
}
monthlyPaymentDisplay.textContent = "$" + totalMonthlyPayment.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
resultDiv.style.display = 'block';
}