Home Mortgage Calculator

This home mortgage calculator is the buyer’s version of the mortgage family. It is built for the moment when you are looking at a specific listing and asking, “What might this home cost each month after taxes, insurance, HOA dues, and PMI?” It starts from the purchase price, not from a standalone loan balance, and it turns a down payment percentage into a mortgage amount automatically.

That buyer-first framing makes it different from the simple mortgage calculator, which strips the problem down to principal and interest only. It also differs from the main mortgage calculator, which lets you enter yearly tax and insurance dollar amounts, toggle PMI, and test extra payments. For a payment-by-payment schedule, use the mortgage amortization calculator. For interest-rate shopping and points, use the mortgage rate calculator.

How the home-price estimate is built

The calculator takes the home price and multiplies it by the down payment percentage. The remaining amount is the loan principal. It then converts the annual interest rate into a monthly rate and applies the fixed-rate amortization formula over the selected term. This produces the principal-and-interest portion of the payment.

Next it estimates property tax from a rate, not from a fixed bill. If the home price is 450,000 dollars and the property-tax rate is 1.2 percent per year, the annual tax estimate is 5,400 dollars and the monthly tax component is 450 dollars. Home insurance and HOA dues are entered as monthly amounts. PMI is calculated only when the down payment is under 20 percent, using the PMI rate entered in the form.

Formula used

The loan amount is:

$\text{loan amount} = \text{home price} - \text{down payment}$

For principal P, monthly interest rate r, and n monthly payments, the standard amortized-payment formula is:

$\text{M} = P \frac{r(1+r)^n}{(1+r)^n-1}$

The all-in monthly estimate shown by this calculator is:

$\text{monthly home payment} = \text{principal and interest} + \text{property tax} + \text{home insurance} + \text{HOA dues} + \text{PMI}$

Total interest is the principal-and-interest payment multiplied by the number of payments, minus the loan amount.

Worked example matching the default form

With the default inputs, the home price is 450,000 dollars and the down payment is 20 percent. The down payment is therefore 90,000 dollars and the loan amount is 360,000 dollars. The interest rate is 6.75 percent for 30 years, so the monthly rate is 0.0675 divided by 12 and the number of payments is 360.

The principal-and-interest payment is 2,334.95 dollars per month. Property tax is calculated from the 1.2 percent annual tax rate: 450,000 dollars times 0.012 equals 5,400 dollars per year, or 450.00 dollars per month. Home insurance is entered as 160.00 dollars per month, and HOA dues are 75.00 dollars per month. Because the down payment is not below 20 percent, PMI is 0.00 dollars.

Add those components and the estimated monthly home payment is 3,019.95 dollars. The total interest over the 30-year term is about 480,583.13 dollars. The result is a useful listing-comparison number, but it is still not the full cost of ownership because it excludes maintenance, utilities, closing costs, furnishings, and future changes in taxes or insurance.

How amortization affects a home shopper

Amortization matters even when this page is focused on the monthly home payment. A fixed mortgage keeps the principal-and-interest payment level, but the split changes every month. In the first years, more of the payment goes to interest because the balance is still high. Later, more goes to principal. That is why a 30-year term usually feels more affordable each month but can generate far more interest than a 15-year term.

Taxes and insurance are different. They do not amortize the loan and they do not build equity. If a lender uses escrow, it may collect these costs monthly and pay the annual bills for you. The calculator uses the values entered today and does not model escrow cushions, shortages, property reassessments after purchase, or insurance premium renewals.

Rate context and buyer tips

A rate quote is not just a national headline number. Lenders price loans based on market conditions, credit score, loan-to-value ratio, occupancy, property type, points, and lock period. A buyer comparing two homes should keep the rate assumption consistent unless there is a specific reason it would change. If the down payment is close to 20 percent, test both sides of the threshold because PMI can change the monthly result.

Use this page with the home affordability calculator when you need an income-based ceiling, the down payment calculator when you are deciding how much cash to put down, and the mortgage calculator with taxes and insurance when you want a more explicit PITI and escrow breakdown. This calculator is informational only and should be checked against a lender’s Loan Estimate before you make an offer or waive contingencies.

Sources

Source version: issuer pages current when accessed July 9, 2026; no unstated effective year is assumed.

• Consumer Financial Protection Bureau, Loan Estimate explainer — projected payment and closing disclosure context.
• Consumer Financial Protection Bureau, Explore interest rates — mortgage-rate comparison assumptions.
• Freddie Mac, Primary Mortgage Market Survey — weekly mortgage-rate market context.
• HUD, Buying a home — homebuyer education and housing-counseling resources.