Mortgage Calculator

How to Use This Mortgage Calculator

Enter your home price and down payment — either as a dollar amount or a percentage — and the calculator will instantly compute your monthly payment. Adjust the interest rate and loan term (10, 15, 20, or 30 years) to see how they affect your payment and total cost. Add property tax, insurance, HOA, and PMI for a realistic all-in monthly figure.

Use the Extra Monthly Payment slider to model prepayment scenarios and see exactly how much interest you'd save and how many months sooner you'd pay off the loan. You can also add one-time lump sum payments to model a bonus, inheritance, or tax refund applied to your principal.

Understanding Your Mortgage Payment

A standard mortgage payment is made up of principal and interest (P&I), calculated using a fixed amortization formula. In the early years of your loan, the majority of each payment goes toward interest rather than principal. This is called front-loaded amortization — it's why extra payments made early in the loan have the biggest impact.

The four components of a full housing payment are often referred to as PITI:

• Principal — the portion of your payment reducing your loan balance
• Interest — the lender's charge for borrowing, highest in early payments
• Taxes — property taxes, typically collected monthly in escrow
• Insurance — homeowner's insurance, also usually escrowed

If your down payment is less than 20% of the home's value, your lender will likely require PMI (private mortgage insurance), which protects the lender in the event of default. PMI is typically 0.5%–1.5% of the loan amount annually and can be removed once you reach 20% equity.

30-Year vs. 15-Year Mortgage

The two most common loan terms are 30 and 15 years. A 30-year mortgage offers lower monthly payments but costs significantly more in total interest — often 2–3× the loan amount over the life of the loan. A 15-year mortgage has higher monthly payments but cuts your total interest roughly in half and builds equity much faster. Use the Compare Loans tab above to run both scenarios side by side with your exact numbers.

How Extra Payments Work

Because a mortgage is front-loaded with interest, every dollar of extra principal you pay reduces the future interest charged on that balance. The effect compounds: paying $200 extra per month on a $400,000 30-year loan at 7% saves roughly $70,000 in interest and cuts about 5 years off the loan. The earlier you start, the bigger the impact — early extra payments reduce the principal base that all future interest is calculated on.

Frequently Asked Questions

• How do I calculate my monthly mortgage payment?
  Your monthly P&I payment uses the formula M = P[r(1+r)^n] / [(1+r)^n−1], where P is the loan amount, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of payments. This calculator handles all of that instantly — just enter your numbers above.
• What is a good LTV ratio for a mortgage?
  LTV (loan-to-value) is your loan amount divided by the home's appraised value. An LTV below 80% (20%+ down payment) eliminates PMI and typically gets you the best rates. Most conventional loans allow up to 97% LTV, but you'll pay PMI on anything above 80%.
• How much do extra mortgage payments save?
  Even $100–$200/month extra can save tens of thousands of dollars in interest over a 30-year loan. Use the Extra Monthly Payment slider above to calculate your exact savings — the calculator shows total interest saved and your new payoff date in real time.
• What is an amortization schedule?
  An amortization schedule shows every payment over the life of your loan — how much goes to principal vs. interest each month, and your remaining balance. Scroll down past the charts to see the full yearly or monthly breakdown for your specific loan.
• When does PMI go away?
  PMI is automatically cancelled when your loan balance reaches 78% of the original home value (per the Homeowners Protection Act). You can also request cancellation when you reach 80% LTV based on current market value — a new appraisal may be required. Paying extra toward principal accelerates this milestone.