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Home Buying Calculators

Buying a home involves more numbers than most first-time buyers expect. Beyond the purchase price, there is the down payment, closing costs, lender fees, prepaid expenses, and ongoing costs that start from day one. Walking into the process with clear numbers means fewer surprises and better negotiating position.

Start with the Home Affordability Calculator to establish your realistic price range before you start viewing properties. It applies the standard 28% front-end debt-to-income ratio lenders use and back-solves from your income, existing debts, and down payment to give you a maximum purchase price — and the expected monthly payment at that price.

Once you have a target price in mind, use the Mortgage Calculator to model the exact monthly payment for any loan amount, interest rate, and term. You can compare 30-year and 15-year options side by side and see the total interest cost over the life of the loan.

Buying calculators

The home buying process — key numbers

The 28/36 rule is the standard lender guideline: spend no more than 28% of gross monthly income on housing (mortgage + taxes + insurance) and no more than 36% on all debt combined (housing plus car loans, student loans, credit cards). Some lenders extend back-end DTI to 43% or higher for well-qualified borrowers.

Down payment and loan-to-value (LTV) affect both your monthly payment and whether PMI applies. At 20% down on a $400,000 home, your loan is $320,000 (80% LTV) — no PMI. At 10% down, your loan is $360,000 (90% LTV) and you will pay PMI until you reach 80% LTV through payments or appreciation.

Points of negotiation: sellers often contribute toward closing costs, especially in buyer's markets. A seller concession of 2–3% on a $400,000 purchase saves $8,000–$12,000 in upfront costs, effectively reducing your cash needed at closing. Factor this into your offer strategy.

Common questions