# Mortgage Calculator

> Estimate principal, interest, taxes, insurance, optional HOA fees, and extra payments.

Page: https://askcalculators.com/calculator/mortgage-calculator/
Definition: https://askcalculators.com/calculator/mortgage-calculator/definition.json
JSON Schema: https://askcalculators.com/calculator/mortgage-calculator/schema.json
Version: 20.1.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/calculator/mortgage-calculator/?homePrice=350000&downPayment=70000&annualRate=6.5&years=30&propertyTax=4200&insurance=1500

## Inputs
- homePrice: Home price; type=money; required; default=350000; min=1
- downPayment: Down payment; type=money; optional; default=70000; min=0
- annualRate: Interest rate; type=percent; required; default=6.5; min=0; max=20
- years: Loan term; type=select; required; default=30; values=10|15|20|30
- propertyTax: Annual property tax; type=money; optional; default=4200; min=0
- insurance: Annual home insurance; type=money; optional; default=1500; min=0
- hoa: Monthly HOA; type=money; optional; min=0
- extraPayment: Extra monthly payment; type=money; optional; min=0

## Outputs
- requiredHousingPayment: Required monthly housing payment; format=currency
- extraPrincipal: Optional extra principal; format=currency
- monthlyPayment: Planned monthly payment with extras; format=currency; primary
- loanAmount: Loan amount; format=currency
- principalInterest: Principal + interest; format=currency
- totalInterest: Total interest; format=currency
- payoffTime: Payoff time; format=text
- totalLoanCost: Principal + interest paid; format=currency

## Formula
M = P × [r(1 + r)ⁿ] ÷ [(1 + r)ⁿ − 1]

- M: monthly principal and interest
- P: loan amount after down payment
- r: monthly interest rate
- n: number of monthly payments

Taxes, insurance, HOA, and extra payment are added after the loan payment is calculated.

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.