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Mortgage Calculator

Estimate your monthly payment, total interest, and view a complete amortization schedule.

This tool breaks down exactly how much your home loan will cost over time by calculating principal and interest based on your loan parameters.

Many basic calculators only show a monthly payment, but this one reveals the full cost of borrowing. By reviewing the amortization schedule, you can see how extra payments reduce interest and shorten your loan duration.

Enter the total principal amount borrowed (home price minus down payment).
Example: Enter 3.75 for a 3.75% annual percentage rate.
Common terms are 15 or 30 years.
Optional — sets accurate dates in the repayment schedule.
Add this amount to reduce your principal balance faster.
Disclaimer: All calculations are estimates intended for personal planning purposes only. Final loan terms depend on your lender, exact closing dates, and potential escrow requirements.

Why This Mortgage Calculator Exists

Many mortgage calculators only show a single monthly number, which can be misleading when planning long-term finances. This tool was built to give a complete picture of your loan by combining monthly payments with a full amortization schedule. It helps you understand how interest builds over time and how small changes like extra payments can significantly reduce your total loan cost.

Understanding Your Mortgage Calculations

Last updated: March 2026

Buying a home is one of the most substantial financial commitments you can make. Whether you are a first-time homebuyer testing out your budget, a real estate investor analyzing cash flow, or a homeowner considering a refinance, having a clear picture of your long-term debt is vital. Our mortgage calculator removes the guesswork, showing you exactly how your payments break down month by month.

When Should You Use This Tool?

  • Budget Planning: Test different home prices and interest rates to see what realistically fits into your monthly household budget.
  • Comparing Loan Terms: Instantly see the long-term cost difference between a 15-year and a 30-year loan.
  • Testing Extra Payments: Find out exactly how much time and interest you save by adding an extra $100 or $200 toward the principal each month.
  • Refinance Estimations: Input your remaining loan balance and a new potential interest rate to determine if refinancing is worth the upfront closing costs.

How This Tool Works

A mortgage payment consists of paying back the money you borrowed (the principal) plus the cost the lender charges you to borrow that money (the interest). Because mortgages stretch across decades, the math involves compound interest calculations that are difficult to do by hand.

When you enter your loan amount, interest rate, and term, the tool figures out the fixed amount you need to pay each month to bring your loan balance to exactly zero by the final payment. It then generates an "amortization schedule." This is simply a table showing every single payment you will make, detailing how much of that payment goes toward interest versus paying down your actual home balance.

Limitations and Accuracy

We strive to provide the most accurate mathematical breakdown of principal and interest. However, it is important to understand the limitations of any online financial calculator:

  • Excludes Escrow Costs: This calculator figures out your core loan payment (Principal & Interest). Your actual monthly bill from your lender will likely include property taxes, homeowners insurance, and possibly private mortgage insurance (PMI). These can significantly increase your total monthly cost.
  • Rounding and Dates: Banks may compound interest slightly differently depending on the exact day of the month your payment posts.
  • Variable Rates: If you have an Adjustable-Rate Mortgage (ARM), this tool will only be accurate for the initial fixed period before the rate changes.

Frequently Asked Questions

Why is most of my payment going toward interest at the beginning?

This is standard for all amortized loans. Interest is calculated based on your total outstanding balance. Since your balance is highest at the beginning of the loan, the interest charge is also at its highest. As you slowly pay down the principal over the years, the interest portion shrinks, and more of your monthly payment goes toward building equity in the home.

Does making an extra payment actually help?

Yes, significantly. Because mortgage interest is calculated on your remaining balance, any extra money you pay goes straight toward the principal. By lowering the principal faster, you reduce the balance that generates interest the following month. Over a 30-year term, even a small extra payment can shave years off your loan and save you tens of thousands in interest.

Should I focus on a 15-year or a 30-year term?

A 30-year term gives you a lower, more manageable monthly payment, which offers financial flexibility if your income changes or if you face unexpected expenses. A 15-year term requires a higher monthly payment, but it secures a lower total interest cost and helps you own the home outright in half the time. The right choice depends entirely on your cash flow comfort level.

What is an amortization schedule?

An amortization schedule is a complete roadmap of your loan. It lists every payment due over the life of the mortgage, detailing the exact amount applied to the principal and the amount applied to interest. It is a helpful document for understanding when you will cross the threshold of paying more toward principal than interest.