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Mortgage Calculator

Calculate your monthly mortgage payment, total interest, and view a full amortization schedule.

Inputs

$
$
6.5%
0%15%
30 years
1 years40 years

Results

Monthly Payment
$1,516.96
Total Payment
$546,106.77
Total Interest
$306,106.77
Loan Amount
$240,000
128% interest-to-principal ratio

Disclaimer: This calculator provides estimates for informational purposes only. Results are not financial advice. Consult a qualified financial advisor for decisions about your specific situation. Actual rates, terms, and conditions may vary by lender and individual circumstances.

How Does the Mortgage Calculator Work?

A mortgage calculator estimates your monthly payment based on the loan amount, interest rate, and loan term using the standard amortization formula. Each monthly payment consists of two parts: principal (paying down what you borrowed) and interest (the cost of borrowing). In the early years, the majority of your payment goes toward interest. As you gradually pay down the principal, the interest portion decreases and the principal portion increases. This is why making extra payments early in the loan term saves the most money — you reduce the principal that earns interest for the remaining 20-30 years. The calculator shows your complete amortization schedule so you can see exactly how each payment is split over the entire life of the loan.

Formula: M = P x [r(1+r)^n] / [(1+r)^n - 1]

How to Use This Calculator

Enter the home price, your down payment amount (or percentage), the mortgage interest rate, and the loan term (typically 15 or 30 years). The calculator instantly computes your monthly principal and interest payment, total interest over the life of the loan, and the total amount paid. Add property taxes and homeowners insurance for a more complete monthly obligation estimate. Use the amortization schedule to see exactly how much principal and interest you pay each month. Experiment with different loan terms and down payment amounts to find the combination that best fits your budget.

Example Calculation

The Johnsons want to buy a $350,000 home with 20% down ($70,000). They are comparing a 30-year fixed mortgage at 6.5% versus a 15-year at 5.9%.

  1. 1Home price = $350,000, Down payment = $70,000 (20%)
  2. 2Loan amount = $280,000
  3. 330-year at 6.5%: Monthly payment = $1,770, Total interest = $357,083
  4. 415-year at 5.9%: Monthly payment = $2,356, Total interest = $144,115
  5. 5Monthly difference = $586 more for 15-year
  6. 6Interest savings with 15-year = $357,083 - $144,115 = $212,968
Result: The 15-year mortgage costs $586 more per month but saves $212,968 in total interest — nearly the amount of the entire loan. The Johnsons would pay $637,083 total with the 30-year versus $424,115 with the 15-year.

Understanding Your Results

Your monthly payment is the fixed amount due each month for principal and interest. Total interest reveals how much you pay beyond the home price for the privilege of borrowing. On a 30-year mortgage, total interest often exceeds the original loan amount. The amortization schedule shows the gradual shift from interest-heavy to principal-heavy payments. In the first year of a 30-year loan at 6.5%, about 75% of each payment goes to interest. By year 20, it flips to about 60% principal. This is why extra payments early in the loan create the biggest savings.

Tips & Best Practices

  • ✓A 15-year mortgage has higher payments but saves tens of thousands in interest compared to a 30-year term.
  • ✓Even small extra payments can shave years off your mortgage. Adding $100/month to a $280,000, 30-year loan at 6.5% saves $57,000 in interest and pays off 4 years early.
  • ✓Keep your total housing costs (mortgage, taxes, insurance) below 28% of gross income.
  • ✓Compare at least 3-5 lenders — rates can vary by 0.5% or more, which adds up to tens of thousands over the life of the loan.
  • ✓Consider points (prepaid interest) if you plan to stay in the home for 5+ years. One point costs 1% of the loan but typically lowers your rate by 0.25%.

Frequently Asked Questions

How is a monthly mortgage payment calculated?▾
Monthly payments are calculated using the amortization formula: M = P x [r(1+r)^n] / [(1+r)^n - 1], where P is the loan principal, r is the monthly interest rate (annual rate divided by 12), and n is the total number of monthly payments. For a $280,000 loan at 6.5% for 30 years: r = 0.065/12 = 0.00542, n = 360, giving a monthly payment of approximately $1,770 for principal and interest.
What is the difference between interest rate and APR?▾
The interest rate is the cost of borrowing the principal amount, expressed as a percentage. APR (Annual Percentage Rate) includes the interest rate plus other costs of the loan such as origination fees, closing costs, and mortgage insurance, giving a more complete picture of the total annual borrowing cost. Always compare APRs between lenders for an apples-to-apples cost comparison.
Should I choose a 15-year or 30-year mortgage?▾
A 15-year mortgage has higher monthly payments but a lower interest rate and saves massive amounts on total interest. A 30-year mortgage offers lower monthly payments and more financial flexibility. Choose a 15-year if you can comfortably afford the higher payment without sacrificing other financial goals. Choose a 30-year if you need the lower payment, but consider making extra principal payments when possible to save on interest.
How much house can I afford?▾
The 28/36 rule suggests spending no more than 28% of gross monthly income on total housing costs (mortgage, taxes, insurance) and no more than 36% on all debt payments. With a $7,000/month gross income, aim for housing costs under $1,960. Use this calculator to find a home price and loan amount where the payment fits within this guideline. Factor in property taxes (typically 1-2% of home value annually) and insurance.
How do extra payments affect my mortgage?▾
Extra payments go directly to reducing your principal balance, which means less interest accrues over time. On a $300,000, 30-year mortgage at 6.5%: adding $200/month saves about $97,000 in total interest and pays off the loan 6.5 years early. Even one extra payment per year (splitting your monthly payment into biweekly payments) saves about $56,000 and shortens the loan by 4.5 years.
By CalcMaven Editorial TeamLast Updated: February 2026

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Free Mortgage Calculator — Monthly Payment & Amortization | CalcMaven