Mortgage Calculator

What Is a Mortgage Calculator?

A mortgage calculator is a financial tool that helps you estimate your monthly mortgage payment before you buy a home. Unlike a simple loan calculator, a full-featured PITI calculator (Principal, Interest, Taxes, and Insurance) shows you every component of your housing payment — giving you the complete picture of what homeownership will actually cost each month.

Our mortgage calculator goes beyond the basics. Enter your home price, down payment, interest rate, and loan term, and it instantly calculates your principal and interest payment, property taxes, homeowners insurance, HOA fees, and PMI — all in one number. You also get a full amortization schedule showing exactly how your loan pays down over time, and an extra payment analyzer showing how much you can save by paying a little more each month.

How to Use This Mortgage Calculator

Using this calculator takes less than 60 seconds. Here is what each input means and how to fill it in:

Home Price: The purchase price of the home. Use the slider or type in the exact amount. Our default is $400,000, close to the current US median home price.
Down Payment: Enter either a dollar amount or a percentage. The two fields sync automatically. A 20% down payment eliminates PMI and gives you more equity from day one.
Interest Rate: The annual interest rate on your mortgage. We pre-fill this with today's average 30-year fixed rate from the Federal Reserve. Your actual rate depends on your credit score and lender.
Loan Term: Choose 10, 15, 20, or 30 years. A shorter term means higher payments but dramatically less interest paid overall.
Property Tax Rate: Annual property taxes as a percentage of the home's value. The national average is about 1.1%. Your actual rate varies by county — check your county assessor's website for the exact rate.
Home Insurance: Annual homeowners insurance premium. The national average is about $1,500/year, but this varies significantly by state, location, and home value.
HOA Fees: Monthly homeowners association fees. Leave at $0 if the home has no HOA.
Extra Monthly Payment: If you plan to pay more than the minimum each month, enter that amount here. The calculator shows exactly how much interest you save and how many years you shave off the loan.

The Mortgage Formula Explained

The principal and interest portion of your payment uses the standard amortization formula:

M = P × [r(1+r)^n] / [(1+r)^n − 1]

Where:
  M = monthly P&I payment
  P = loan amount (home price − down payment)
  r = monthly interest rate (annual rate ÷ 12 ÷ 100)
  n = total payments (loan term in years × 12)

Your total monthly payment (PITI) adds property taxes, insurance, PMI (if applicable), and HOA fees on top of this base payment.

Worked Example

Let's say you are buying a $400,000 home with 20% down ($80,000), a 6.82% interest rate, 30-year term, 1.2% property tax, and $1,500/year insurance:

Loan Amount: $400,000 − $80,000 = $320,000
Monthly Rate: 6.82% ÷ 12 = 0.5683%
P&I Payment: $320,000 × [0.005683 × (1.005683)^360] / [(1.005683)^360 − 1] = $2,086/mo
Property Tax: $400,000 × 1.2% ÷ 12 = $400/mo
Insurance: $1,500 ÷ 12 = $125/mo
Total PITI: $2,086 + $400 + $125 = $2,611/mo
Total Interest Over 30 Years: $431,676

What Factors Affect Your Mortgage Payment?

Five variables determine your mortgage payment, and understanding each one gives you leverage to lower your payment:

Home Price: The single biggest driver. A $50,000 lower purchase price saves roughly $300–400/month in combined PITI.
Down Payment: A larger down payment reduces your loan balance, eliminates PMI above 20%, and lowers your monthly payment. Going from 5% to 20% down on a $400,000 home saves about $200/month in P&I alone, plus eliminates ~$133/month in PMI.
Interest Rate: A 1% difference on a $300,000 loan changes your payment by about $170/month. Improving your credit score from 640 to 760 could save you 0.5%–1.0% on your rate.
Loan Term: A 15-year mortgage on a $300,000 loan at 6.5% costs $2,613/month vs. $1,896 for a 30-year — but saves $173,000 in total interest.
Location (taxes and insurance): Property tax rates range from under 0.3% (Hawaii) to over 2.4% (New Jersey). This alone can swing your total monthly payment by $500+.

Tips to Save Money on Your Mortgage

Shop at least 3 lenders. CFPB research shows that getting just one additional rate quote saves the average buyer $1,500 over the loan's life. Getting five quotes saves $3,000+.
Improve your credit score before applying. A score above 760 gets the best rates. Paying down credit cards below 30% utilization and removing errors from your report can raise your score in 30–60 days.
Make bi-weekly payments. Instead of 12 monthly payments, make 26 half-payments per year. This results in one extra full payment per year, cutting a 30-year mortgage to about 26 years and saving tens of thousands in interest.
Avoid PMI with 20% down. PMI costs 0.5%–1.5% of the loan balance per year — $1,600–$4,800/year on a $320,000 loan. Worth avoiding if you have the down payment available.
Buy points strategically. Mortgage discount points cost 1% of the loan amount and lower your rate by roughly 0.25%. They are worth buying if you plan to stay in the home past the break-even point (typically 3–5 years).
Consider an ARM if you'll move in <7 years. A 5/1 or 7/1 ARM typically offers a lower rate than a fixed mortgage for the initial period. If you plan to sell before the adjustment period, you may save significantly.

Frequently Asked Questions

PITI stands for Principal, Interest, Taxes, and Insurance — the four components of a typical mortgage payment. Some payments also include PMI (Private Mortgage Insurance) and HOA fees.

Your principal and interest 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, and n is the number of payments.

Private Mortgage Insurance (PMI) is required when your down payment is less than 20% of the home's purchase price. It typically costs 0.5%–1.5% of the loan amount per year.

A common guideline is to keep your total housing payment (PITI) below 28% of your gross monthly income. Use our Mortgage Affordability Calculator for a personalized estimate.

As of 2026, the average 30-year fixed mortgage rate is around 6.5%–7%. The rate you get depends on your credit score, down payment, loan type, and lender.

A 15-year mortgage has higher monthly payments but significantly less total interest paid. A 30-year mortgage has lower monthly payments, giving you more financial flexibility. Use our calculator to compare both scenarios.

Extra payments reduce your principal faster, shortening your loan term and saving you thousands in interest. Even $100/month extra can cut years off a 30-year mortgage.

An amortization schedule shows each monthly payment broken down into principal and interest portions, plus the remaining loan balance after each payment.

While 20% avoids PMI, many loans accept 3%–5% down. A larger down payment reduces your monthly payment and total interest paid significantly.

Often yes — most lenders require an escrow account that collects 1/12 of your annual property tax and insurance each month along with your P&I payment.

Related Calculators

After calculating your mortgage payment, these tools help you make a complete picture of your homebuying decision:

Mortgage Affordability Calculator — Find the maximum home price based on your income and debts
Refinance Calculator — Calculate your break-even point and savings from refinancing
HELOC Calculator — See how much equity you can access after purchasing
Income Tax Calculator — Estimate taxes alongside your housing budget

Payment Breakdown

Balance vs. Interest Over Time

Amortization Schedule