Mortgage Calculator

Calculate PITI monthly payments with amortization schedules, and estimate how much home you can afford based on income and debt ratios.

Modify the values and click the Calculate button to use this tool.

PITI Mortgage Calculator

Full monthly housing payment: Principal, Interest, Taxes, and Insurance (PITI) on a fixed-rate home loan.

Modify the values and click the Calculate button to use this tool.

Home Affordability Calculator

Estimate the maximum loan amount based on gross monthly income, existing debt, and a front-end housing ratio.

Formulas

EMI = P × r(1+r)n / ((1+r)n − 1)
PITI = EMI + tax/12 + insurance/12

How to use this mortgage calculator

  1. PITI: Enter loan amount, interest rate, term, annual property tax, and home insurance to get your full monthly housing payment.
  2. Review breakdown: See principal & interest vs total interest paid, plus an amortization schedule and chart.
  3. Affordability: Enter monthly income, other debt payments, rate, term, and max housing ratio to estimate the largest loan you can support.

Mortgage formulas

EMI (monthly P&I) = P × [r(1+r)n] / [(1+r)n − 1]
PITI = EMI + (property tax / 12) + (insurance / 12)
Max loan = max P&I × [(1+r)n − 1] / [r(1+r)n]

Where P is loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is total months. PITI adds escrowed tax and insurance to principal and interest.

Real-world uses

  • Home shopping: Compare monthly PITI across listings before making an offer.
  • Refinancing: Model how a lower rate or shorter term changes payments and total interest.
  • Budget planning: Use the affordability panel with the 28% front-end ratio common in lending guidelines.
  • Amortization review: See how much of each year's payments go to interest vs principal over a 30-year term.

Frequently Asked Questions

PITI stands for Principal, Interest, Taxes, and Insurance — the four components of a typical monthly mortgage payment. Principal and interest repay the loan; taxes and insurance are often escrowed by the lender.

The EMI (equated monthly installment) formula spreads the loan principal plus interest evenly over n monthly payments at rate r. It is the same formula used for auto loans and personal loans on fixed terms.

The 28% rule suggests spending no more than 28% of gross monthly income on housing (P&I). Lenders also consider total debt (including car loans and credit cards) against income — often capped around 36–43%.