Mortgage Calculator
WEBEstimate your monthly home loan payment, total interest and total cost.
Down payment: $70,000 (20%)
Principal and interest only. Property tax, insurance and HOA fees are not included — estimates only, not financial advice.
What is the Mortgage Calculator tool?
This mortgage calculator turns a home price, down payment, interest rate and loan term into the numbers that actually matter when you buy: your monthly principal-and-interest payment, the loan amount you finance, the total interest you pay over the life of the loan, and the total cost of the house once interest is added. Enter the down payment either as a percentage of the price or as a fixed cash amount — the tool converts between the two and caps it at the price so the loan can never go negative.
Under the hood it uses the standard amortization formula, the same math a bank or a spreadsheet uses: the loan is the price minus your down payment, and the monthly payment is what fully repays that loan across every month of the term at the given rate. If you set the rate to zero, the payment simply divides the loan evenly across the months. A split bar shows at a glance how much of your total cost is principal versus interest — which is often eye-opening, because on a long term the interest can rival the price of the home itself.
Everything runs on your device: your price, deposit and rate are never uploaded, stored or shared, and no account is needed. It works on your phone, switches between a percent and a cash down payment in one tap, and copies or shares the result. One honest note: this figure is principal and interest only. Property taxes, homeowners insurance, mortgage insurance (PMI) and HOA fees are not included, so your real monthly housing cost will be higher — treat this as a fast estimate to compare scenarios, not a loan quote or financial advice.
How to use the Mortgage Calculator
- Enter the home price.
- Enter your down payment — toggle between a percentage of the price and a fixed cash amount.
- Type in the annual interest rate.
- Set the loan term in years with the slider.
- Read your monthly payment, loan amount, total interest and total cost — they update instantly. Copy or share the result.
Frequently asked questions
How is the monthly mortgage payment calculated?
It uses the standard amortization formula: M = P × r × (1 + r)^n ÷ ((1 + r)^n − 1), where P is the loan amount (price minus down payment), r is the monthly interest rate (annual rate ÷ 12), and n is the number of monthly payments (years × 12). A 0% rate simply splits the loan evenly across the months.
Does this include property tax and insurance?
No. The figure is principal and interest only. Property taxes, homeowners and mortgage insurance (PMI), and HOA fees are not included, so your actual monthly housing cost will be higher. This tool is meant for quickly comparing loan scenarios, not for a full escrow estimate.
How much difference does the down payment make?
A bigger down payment lowers the amount you finance, which lowers both the monthly payment and the total interest you pay over the term. You can enter it as a percentage or a cash amount and watch the loan amount and interest change instantly. A larger down payment can also help you avoid mortgage insurance.
Can I compare a 15-year and a 30-year term?
Yes. Drag the term slider and the payment recalculates. A shorter term raises the monthly payment but cuts the total interest sharply; a longer term lowers the monthly payment but you pay far more interest over time. The split bar makes that trade-off easy to see.
Is my data private?
Yes. The price, down payment and rate are processed entirely in your browser — nothing is uploaded, stored or sent to any server, and no sign-up is required. Once the page has loaded, the calculator even works offline.
Is this mortgage calculator free?
Yes — free, with no account and no limits. Open the page and estimate a payment in seconds.