Mortgage Calculator — Real Cost with Tax & Insurance

Enter Parameters

Adjust sliders or type values directly

Home Price

Down Payment

Interest Rate

Loan Term

years

Annual Property Tax

$/yr

Annual Home Insurance

$/yr

Real-time Calculation Ready

Adjust parameters to see instant results

AI Summary & Key Formula

Mortgage Calculator Quick Reference

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Quick Answer

A mortgage calculator returns your monthly housing payment: principal and interest from the amortization formula M = P × r × (1 + r)ⁿ / ((1 + r)ⁿ − 1), plus one-twelfth of your annual property tax and home insurance. For example, a $400,000 home with $80,000 down at a 6.5% 30-year fixed rate, with $4,000 property tax and $1,200 insurance a year, costs $2,456 a month ($2,023 of it principal and interest) and $408,142 in interest over the loan. Use it to compare rates, terms and down payments; it assumes a fixed rate and excludes PMI and HOA fees.

How This Calculation Works

Values calculate dynamically in real-time as you enter figures or adjust sliders.
The equation on the right is exactly what the calculator runs — check any result by hand.

Core Equation

Monthly P&I = P × r × (1 + r)ⁿ / ((1 + r)ⁿ − 1)

Total Monthly Payment = P&I + (Property Tax / 12) + (Insurance / 12)

Where:
  P = Loan amount (home price − down payment)
  r = Monthly interest rate
  n = Loan term in months

Not included: PMI (usually 0.5–1.5% of the loan per year when the down payment is under 20%) and HOA fees.

How to Use the Mortgage Calculator

Quick 3-step guide for accurate and fast calculations

STEP 01

Enter your home price

In the Mortgage Calculator, fill in Home Price, Down Payment, Interest Rate, Loan Term, Annual Property Tax and Annual Home Insurance.

STEP 02

Read your total monthly payment

The Mortgage Calculator instantly shows Total Monthly Payment, Monthly Principal & Interest, Monthly Property Tax and Monthly Home Insurance, updating as you type.

STEP 03

Compare scenarios

Change Down Payment to see how it affects Total Monthly Payment, then check the formula below to verify the math.

Specific Instructions:

Enter the home price, your down payment amount, annual interest rate and loan term in years. Add annual property tax and homeowner's insurance for a complete picture; PMI and HOA dues are not included, so add them separately if they apply. The calculator returns your total monthly payment split into principal and interest, property tax and insurance, plus the loan amount, total interest and total cost over the life of the loan.

Mortgage Calculator Formula

The Mortgage Calculator uses the following formula, calculated in your browser as you change the inputs:

Monthly P&I = P × r × (1 + r)ⁿ / ((1 + r)ⁿ − 1) Total Monthly Payment = P&I + (Property Tax / 12) + (Insurance / 12) Where: P = Loan amount (home price − down payment) r = Monthly interest rate n = Loan term in months Not included: PMI (usually 0.5–1.5% of the loan per year when the down payment is under 20%) and HOA fees.

Sources:

Worked Example: Mortgage Calculator

Calculations run in your browser — your inputs are never stored on our servers.Formula sources & methodology

Frequently Asked Questions — Mortgage Calculator

What is PMI and when is it required?

PMI (Private Mortgage Insurance) is required by most lenders when your down payment is less than 20% of the home price. It protects the lender if you default. PMI typically costs 0.5–1.5% of the loan amount per year and is added to your monthly payment until you reach 20% equity.

Should I choose a 15-year or 30-year mortgage?

A 15-year mortgage has higher monthly payments but you pay significantly less total interest and build equity faster. A 30-year mortgage has lower payments, freeing up cash for other investments. If the monthly difference can be invested at a return higher than your mortgage rate, the 30-year may be better financially.

How does the interest rate affect my monthly payment?

Even small rate changes have a large impact because the rate applies to the whole balance for decades. On a $300,000 30-year loan, moving from 6% to 7% raises monthly principal and interest from $1,799 to $1,996, about $197 more a month, and increases total interest from $347,515 to $418,527, roughly $71,000 over the life of the loan. That is why comparing quotes even 0.25% apart is worthwhile.