Mortgage Calculator
Estimate your full monthly mortgage payment — principal, interest, property tax, homeowners insurance and PMI — and see the complete amortization schedule for the life of the loan.
How to use the Mortgage Calculator
- Enter your inputs into the Mortgage Calculator above.
- Results update instantly as you type — no submit button needed.
- Adjust any value to see how the result changes in real time.
The mortgage payment formula
M = P · r(1 + r)^n / ((1 + r)^n − 1)
P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments (loan term in years × 12). The result M is the fixed monthly principal-and-interest payment for a standard fixed-rate mortgage.
Worked example
A $300,000 mortgage at 6.5% APR over 30 years gives r = 0.065 / 12 ≈ 0.005417 and n = 360. Plugging in: M ≈ $1,896.20 per month for principal and interest. Over the full term you pay back about $682,633 — roughly $382,633 in interest.
Frequently asked questions
What does this mortgage calculator include?
It calculates principal and interest using a standard amortization formula. You can add property tax, homeowners insurance and PMI to see your full PITI payment and the total cost of the loan.
How does the down payment affect my payment?
A larger down payment lowers the loan principal directly, which reduces every monthly payment proportionally. Putting down 20% or more on a conventional loan also lets you skip private mortgage insurance (PMI).
Should I choose a 15-year or 30-year term?
A 15-year mortgage has higher monthly payments but a much lower interest rate and far less total interest. A 30-year mortgage has lower monthly payments and is easier to qualify for but costs significantly more over the life of the loan.
How much can extra payments save me?
Even small extra principal payments shorten the loan term and reduce total interest, because they cut into principal that would otherwise compound for years. Use the amortization schedule to see the impact of any extra payment.