Loans & savings
Mortgage Calculator
Enter the home price, your down payment and the rate you've been quoted. The payment shown is the full monthly cost: principal and interest from the loan, plus the tax, insurance and HOA amounts you add.
Your result will appear here.
How it's calculated
The principal and interest part uses the standard loan payment formula, where P is the loan amount (price minus down payment), r is the yearly rate divided by 12 and n is the number of monthly payments.
Property tax and insurance are divided by 12 and added on top, because most lenders collect them each month into an escrow account. PMI is not included; if your down payment is under 20%, ask your lender for that figure and add it to the HOA box.
Payment = P × r × (1 + r)^n ÷ ((1 + r)^n − 1)
How to do it in Excel
With the loan amount in B1, the yearly rate in B2 and the term in years in B3:
=PMT(B2/12, B3*12, -B1)- Monthly principal and interest. The minus sign makes the result positive.
=PMT(B2/12, B3*12, -B1) + (B4+B5)/12 + B6- Full payment, with yearly tax in B4, yearly insurance in B5 and monthly HOA in B6.
Questions
How much does a 1% lower rate save?
On a $320,000 loan over 30 years, going from 6.5% to 5.5% cuts the monthly principal and interest by about $205, and saves roughly $74,000 in interest over the life of the loan.
Should I pick a 15-year or 30-year term?
A 15-year loan has a higher monthly payment but far less total interest. Switch the term above and compare the total interest line to see the gap for your numbers.