A mortgage calculator helps you estimate your monthly home loan payment and understand the true cost of buying a home. By entering the home price, down payment, interest rate, and loan term, you can see exactly how much you will pay each month — including principal, interest, property taxes, insurance, and PMI — so you can budget with confidence before making the biggest purchase of your life.
Mortgage Details
20.0% of home price
Additional costs (taxes, insurance, PMI)
Applied only if down payment < 20%
How to Use the Mortgage Calculator
Buying a home is one of the biggest financial decisions you will ever make. This free mortgage calculator helps you estimate your monthly payment and total cost so you can plan your budget with confidence before house hunting or making an offer.
Step 1: Enter the Home Price
Start by entering the asking price or expected purchase price of the home. This is the total property value before any down payment. You can adjust this number to explore different price ranges and see how they affect your monthly payment.
Step 2: Set Your Down Payment
Enter your down payment as a dollar amount or toggle to a percentage. The industry standard is 20%, which avoids PMI (Private Mortgage Insurance). Toggle between dollar and percentage modes to quickly see how different down payment amounts change your loan. If your down payment is below 20%, PMI will automatically be included in your payment breakdown.
Step 3: Choose Interest Rate and Loan Term
Enter the annual interest rate offered by your lender. Then select a loan term — common options are 15, 20, 25, or 30 years. You can also type a custom term. Shorter terms mean higher monthly payments but significantly less total interest paid over the life of the loan.
Step 4: Add Taxes, Insurance, and PMI (Optional)
Expand the additional costs section to include annual property tax and homeowner's insurance. These are added to your monthly payment to give you a realistic picture of your total monthly housing cost. The PMI rate field is pre-filled at 0.5% and applies automatically when the down payment is under 20%.
Step 5: Review Your Results
Click "Calculate Payment" to see your estimated monthly payment with a full breakdown. The pie chart visualizes how your payment splits between principal and interest, taxes, insurance, and PMI. The amortization summary shows total principal vs. total interest over the life of the loan. Finally, the 15-year vs 30-year comparison table helps you understand the tradeoffs between lower monthly payments and long-term savings.
For a detailed walkthrough, see our guide: Mortgage Down Payment Strategies: 5%, 10%, or 20%?.
FAQ
Is this mortgage calculator free?
Yes, this mortgage calculator is completely free with no hidden fees, no signup, and no limits. You can run unlimited calculations and compare different scenarios at no cost. Everything runs entirely in your browser.
Is my financial data safe?
Absolutely. All calculations run entirely in your browser using client-side JavaScript. Your mortgage details are never sent to any server or stored in any database. You can verify this by disconnecting from the internet — the calculator continues to work perfectly.
How is the monthly mortgage payment calculated?
The monthly payment is calculated using the standard amortization formula: M = P[r(1+r)^n] / [(1+r)^n - 1], where P is the loan amount (home price minus down payment), r is the monthly interest rate (annual rate divided by 12), and n is the total number of monthly payments. Property tax, insurance, and PMI are then added on top.
What is PMI and when do I have to pay it?
PMI (Private Mortgage Insurance) is required when your down payment is less than 20% of the home price. It protects the lender if you default on the loan. PMI typically costs 0.5% to 1% of the loan amount annually. Once you reach 20% equity, you can request PMI removal.
Should I choose a 15-year or 30-year mortgage?
A 15-year mortgage has higher monthly payments but saves you significantly on total interest — often hundreds of thousands of dollars. A 30-year mortgage offers lower monthly payments, giving you more cash flow flexibility. Use the comparison feature to see the exact difference for your situation.
How much should my down payment be?
While 20% is the traditional recommendation to avoid PMI, many loan programs accept 3-10% down. A larger down payment means a smaller loan, lower monthly payments, and no PMI. Use this calculator to compare different down payment scenarios and see how each affects your total cost.
Does this calculator include property taxes and insurance?
Yes. You can enter your annual property tax and homeowner's insurance amounts as optional fields. The calculator adds these to your monthly payment breakdown so you can see your true total monthly housing cost, not just principal and interest.
How accurate is this mortgage calculator?
This calculator uses the same standard amortization formula used by banks and lenders. The results are highly accurate for fixed-rate mortgages. Keep in mind that actual costs may vary slightly due to escrow adjustments, HOA fees, or changes in tax and insurance rates over time.