What goes into the payment
Start with the price and the down payment. The rest is the loan, and the calculator works out principal and interest on it at the rate and term you pick. Then it adds what sits on top:
- Property tax: a yearly amount or a percent of the price. In Michigan, plan with the bill after the sale: the year after a Michigan home sells, its taxable value resets to half of the assessor's market value, so the seller's tax bill is not your tax bill. Get the published rate for an address.
- Homeowners insurance: a planning figure until you have an agent's quote.
- HOA dues: the monthly amount, if the home has an association.
- PMI: added on a conventional loan when the loan is more than 80% of the price, at the percent in the PMI field.
When you change the price, the down payment, tax and insurance keep the figure you typed, in dollars or as a percent, and the rest is worked out again.
Mortgage formula
M = P × r(1 + r)n ÷ ((1 + r)n − 1)
M is the monthly principal and interest, P the loan amount, r the monthly interest rate (the annual rate divided by 12) and n the number of monthly payments.
The calculator above works this out at the rate you pick, then adds tax, insurance, HOA dues and any PMI.
