Mortgage Calculator

A mortgage calculator answers the question every homebuyer needs answered before making an offer: what will this actually cost me each month? This mortgage calculator uses the standard amortization formula to compute your monthly principal and interest, then adds optional property tax, homeowners insurance, PMI, and HOA fees to produce a realistic total monthly housing payment — not just the P&I component that most calculators show. Loan terms of 10, 15, 20, and 30 years are all supported. Whether you are buying your first home, comparing loan terms, or running refinance scenarios, this mortgage payment calculator gives you the complete picture in seconds. All inputs update instantly with no page reload required.

How to Use the Mortgage Calculator

• Enter the home price — the purchase price before any down payment.
• Enter your down payment — the cash you are putting down upfront.
• Enter the annual interest rate as a percentage (e.g. 6.5 for 6.5%).
• Select your loan term: 10, 15, 20, or 30 years.
• Optionally enter annual property tax, annual homeowners insurance, monthly PMI, and monthly HOA fees to see your full estimated housing payment.
• Click "Calculate Mortgage" to see the full breakdown instantly.

Mortgage Example: $400,000 Home at 6.5%

A buyer purchases a $400,000 home with $80,000 down (20%), financed at 6.5% APR. The loan amount is $320,000. Here is how the two most common mortgage loan terms compare:

The 15-year mortgage saves $226,620 in interest over the life of the loan, but requires $764 more per month. Whether that tradeoff makes sense depends on your cash flow, investment options, and how long you plan to stay in the home.

When Would You Use This?

Setting a home purchase budget. Before making any offer, use this mortgage calculator to find the maximum price that produces a monthly payment you are comfortable with. Work backward: enter your target total monthly housing cost, then adjust home price and down payment until the numbers align with your budget.

Comparing 15-year vs. 30-year mortgages. The interest difference between these two terms on the same loan can be hundreds of thousands of dollars. Running both scenarios side by side makes that cost concrete — the table above shows $226,620 saved on a single $320,000 loan. Seeing the actual dollars is more persuasive than any rule of thumb.

Estimating your full PITI payment. Lenders qualify borrowers on PITI — principal, interest, taxes, and insurance. Using the optional fields for property tax, homeowners insurance, PMI, and HOA fees gives you the realistic monthly payment that matters for qualifying, budgeting, and comparing homes at different price points with different tax rates.

Frequently Asked Questions

How is a monthly mortgage payment calculated?

Monthly mortgage payments use the standard amortization formula: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan principal, r is the monthly interest rate (annual rate divided by 12), and n is the number of monthly payments (years × 12). For a $320,000 loan at 6.5% over 30 years, the monthly principal and interest payment is approximately $2,023. The same loan over 15 years produces a monthly payment of about $2,787 — $764 more per month in exchange for paying off the loan in half the time and saving over $226,000 in interest.

What is the difference between principal and interest?

Principal is the loan balance — the amount you borrowed that decreases with each payment. Interest is the lender's fee, calculated each month as a percentage of the remaining balance. Because your balance is highest at the start of the loan, early payments are mostly interest with little going to principal. This shifts gradually over time — by the final years of a 30-year mortgage, nearly all of each payment reduces the principal. Making extra principal payments early saves a disproportionately large amount of interest because it reduces the balance used to calculate future interest charges.

Should I choose a 15-year or 30-year mortgage?

A 15-year mortgage builds equity faster and costs significantly less in total interest — on a $320,000 loan at 6.5%, it saves $226,620 versus the 30-year option. The tradeoff is a higher required monthly payment ($764 more per month in this example), which reduces cash flow flexibility. A 30-year mortgage lowers your required payment, which is useful if you want to keep monthly obligations manageable or deploy extra cash elsewhere. Neither is universally better — the right choice depends on your income stability, other financial goals, and how long you plan to stay in the home.

What is PMI on a mortgage?

PMI stands for Private Mortgage Insurance. Most lenders require it when the down payment is less than 20% of the home's purchase price. PMI protects the lender in the event of default — it does not provide any benefit to the borrower. The cost typically runs 0.5% to 1.5% of the loan amount per year, added to your monthly payment. On a $320,000 mortgage at 1%, PMI adds roughly $267 per month. PMI is not permanent — it can be canceled once your loan balance reaches 80% of the home's original purchase price, or sooner if the home has appreciated and you request a new appraisal.

How does the down payment affect a mortgage?

Every additional dollar in your down payment is a dollar you do not borrow — and a dollar you do not pay interest on for the entire loan term. On a $400,000 home, increasing the down payment from 10% ($40,000) to 20% ($80,000) reduces the loan by $40,000 and eliminates the PMI requirement entirely. At 6.5% over 30 years, that $40,000 loan reduction saves approximately $51,000 in interest alone — in addition to any PMI savings. A larger down payment also typically qualifies you for a lower interest rate, compounding the savings further.