Mortgage Calculator
Estimate monthly payments and total interest for your buyer clients.
Fill in the details and click Calculate.
What the calculator shows
Enter the purchase price, down payment, interest rate and term and the calculator returns the monthly payment, broken into its parts. Seeing principal and interest separately from taxes and insurance matters, because buyers who have only ever been quoted a principal-and-interest figure are routinely surprised by what actually leaves their account each month.
It is built to be used in front of a client rather than to produce a document for a file. The common moment is a buyer standing in a property asking what it would cost, or a seller weighing whether their next purchase is affordable. Having the answer in seconds, with the components visible, keeps the conversation moving.
The parts of a payment buyers underestimate
Principal and interest is the part everyone quotes. Property taxes vary enormously by location and are frequently the single largest addition. Homeowner's insurance is required by lenders and costs more in some areas than buyers expect. Mortgage insurance usually applies below a twenty percent down payment and is a real monthly cost rather than a technicality. Where a property sits in an HOA, those dues are a further monthly obligation that no mortgage calculation includes.
The gap between a principal-and-interest quote and the true monthly cost is what derails buyers late in a purchase. Setting the expectation early — that the headline figure is a component and not the total — is one of the more useful things an agent does in a first conversation, and it is a conversation that goes better with a number on the screen.
How rate and down payment move the number
Two levers dominate. A change in interest rate alters the monthly payment across the entire term, which is why a rate move of a point or so can reprice what a buyer can afford far more sharply than a change in the asking price. A larger down payment reduces the amount borrowed and, past the usual twenty percent threshold, typically removes mortgage insurance as well — so it often improves the monthly figure twice over.
Running two or three scenarios side by side is usually more useful than one precise calculation. A buyer who can see what happens at their current savings level, at a slightly higher one, and at a different price point makes a better decision than one handed a single number. It also turns an abstract budget conversation into a concrete one.
What it is and is not
This is an estimating tool for conversations, not a lending decision. It does not check credit, verify income, apply a specific lender's underwriting or produce a rate anyone is committed to. Actual rates depend on credit profile, loan type, property type and the lender, and the only number that counts is the one in a written quote.
Use it to frame the conversation and then send the buyer to a lender for pre-approval. An agent who sets realistic expectations early and hands off to a lender promptly has a buyer who can act when the right property appears — which is worth considerably more than a precise-looking estimate.
Every tool on Agent Copilot AI is included in one $29-per-month plan with unlimited use, rather than being billed per image or per document. There is a 7-day free trial and no credit card is required to start, so you can run a real listing through it before deciding.
Frequently Asked Questions
What does the monthly figure include?
It breaks the payment into its parts so principal and interest are visible separately from taxes and insurance. That distinction is where buyers quoted only a principal-and-interest number get surprised.
Why does the interest rate matter so much?
A rate change affects the payment across the whole term, so a move of around a point can reprice what a buyer can afford more sharply than a change in the asking price.
Does a bigger down payment help twice?
Often. It reduces the amount borrowed, and past the usual twenty percent threshold it typically removes mortgage insurance as well, so the monthly figure improves on two counts.
Does this include HOA dues?
Mortgage calculations do not include HOA dues, and where a property has them they are a real monthly obligation on top. Factor them in separately when comparing properties.
Is this a pre-approval?
No. It is an estimate for conversation. Actual rates depend on credit, loan type, property type and lender, and only a written quote from a lender is binding. Use it to frame the discussion, then refer the buyer for pre-approval.
Related tools
More AI tools built for real estate agents.
Rent vs. buy calculator
Help clients decide if buying makes financial sense over renting.
Seller's net sheet
Show sellers exactly how much they'll walk away with at closing.
AI CMA generator
Build a client-ready comparative market analysis in minutes.