Mortgage Calculator - Monthly Payment & Amortization Schedule

How to use this tool

1. Choose your calculator mode. Use "Calculate Payment" to estimate your monthly payment for a specific home price, or switch to "What Can I Afford?" to find your maximum home price based on your income and debts.
2. Enter the home price. Type the purchase price of the home you are buying. Property tax and home insurance will be estimated automatically based on the home price and your selected state.
3. Enter the down payment. Enter your down payment as a dollar amount or click "Switch to %" to enter it as a percentage — the calculator converts between the two automatically. A 20% down payment avoids PMI.
4. Select your state. Choose your state to get a more accurate property tax estimate based on your state's average effective tax rate. You can override the estimate with your actual tax bill at any time.
5. Set the interest rate and term. Enter the annual interest rate from your lender. Choose the loan term — 30 years is most common; 15 years builds equity faster with a higher payment.
6. Review PMI and optional costs. If your down payment is less than 20%, PMI is automatically estimated. Expand "Add insurance, HOA & extra payment" to review estimated costs, override them, or add HOA fees and extra principal. The results estimate interest and payoff time saved by recurring extra principal.
7. View the amortization schedule. Click "View amortization schedule" to see a year-by-year or month-by-month breakdown. The month when PMI becomes eligible for cancellation is highlighted in green.

How to use the mortgage calculator

Choose between Calculate Payment (enter a home price, get your monthly payment) and What Can I Afford? (enter your income and debts, get a maximum home price). Enter the home price, down payment, interest rate, and loan term. Property tax and home insurance are estimated automatically from your state's average rates — you can override either value. Conventional PMI is estimated when your down payment is less than 20%. Expand "Add insurance, HOA & extra payment" to fine-tune costs. View the full amortization schedule with the PMI cancellation month highlighted.

How a mortgage payment is calculated

The principal and interest (P&I) portion uses the standard amortization formula:

M = P × r(1+r)ⁿ / ((1+r)ⁿ − 1)

where M is the monthly P&I payment, P is the loan principal (home price minus down payment), r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments. When the interest rate is 0%, the payment simplifies to P ÷ n.

What goes into a monthly mortgage payment (PITI)

Most lenders collect your full PITI payment each month and place the non-P&I portions into an escrow account:

• Principal: reduces your loan balance
• Interest: the cost of borrowing
• Taxes: property taxes (typically paid annually from escrow)
• Insurance: homeowners insurance (typically paid annually from escrow)
• PMI: conventional loans often require it below 20% down; other loan types may use different mortgage insurance rules

How extra principal payments reduce your loan

Every dollar of extra principal you pay goes directly toward reducing your loan balance, which means you accrue less interest the following month. A consistent extra payment of even $100–$200 per month can shave years off a 30-year mortgage and save tens of thousands of dollars in interest. Use the "Extra principal payment" field to model the savings.

The calculator shows the required monthly payment separately from the planned monthly outflow when you add extra principal. Extra principal is optional and goes directly to the loan balance, so it is not part of the required lender payment. The displayed payoff month is the month of the final scheduled payment.

Common mortgage payment examples

These examples use the same fixed-rate principal-and-interest formula as the calculator above. They exclude property tax, homeowners insurance, PMI, and HOA fees, which depend on the home and loan details.

ARM vs fixed-rate mortgages

A fixed-rate mortgage keeps the same interest rate for the full term, which is the loan type this calculator models. An adjustable-rate mortgage (ARM) starts with a fixed-rate period and later adjusts under the contract's schedule, index, margin, and rate caps. This calculator does not model those future changes, so its payment and payoff estimates should not be used to compare an ARM's later payments. Review the lender's adjustment terms or use an ARM-specific calculator for that comparison.

Refinance break-even

When refinancing, you typically pay closing costs of 2–5% of the loan amount. The break-even period tells you how long you must stay in the home to recoup those costs:

Break-even months = Closing costs ÷ Monthly savings from lower payment

For example, $5,000 in closing costs and $150/month in savings -> break-even in ~33 months. If you plan to sell before then, refinancing likely isn't worthwhile.