You can adjust each input to reflect what you're paying on your house. Or, if you're in the process of buying a house, you can adjust to find a sweet spot for a home on which extra payments might benefit you.

The loan type is whether this is a new loan or an existing loan for a house you already own.
The purchase price is the amount you and your seller agree you'll pay for the house. This isn't the same as the loan amount, which typically is at most 80% of the total cost, plus interest.
The down payment is what you pay toward the loan to cover the purchase price.
A term, or loan term, is how long it'll take to pay off the loan, typically between 10 or 30 years.
The interest rate is a percentage of the loan amount that you pay monthly.
Extra payments are the additional monthly payments you plan to make each month to help save on your mortgage.
Property tax is charged by local governments to cover public services and property.
Homeowners insurance is required by most lenders. It protects your house, standalone structures, personal belongings and you and your family members' liability.
Private mortgage insurance (PMI) is typically required by lenders if your down payment is less than 20%. This helps assure that you take on enough risk in case you miss a payment.