Mortgage Calculator
Calculate monthly payment, total interest, and full loan cost for any home mortgage.
View Year-by-Year Amortization
| Year | Principal | Interest | Balance |
|---|
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How to Calculate a Mortgage Payment
The standard formula for a fixed-rate mortgage monthly payment is:
M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]
Where P = loan amount, r = monthly interest rate (annual ÷ 12), and n = total payments (years × 12). On a $320,000 loan at 6.5% for 30 years: r = 0.065/12 = 0.005417, n = 360, M ≈ $2,022/month.
How Down Payment Affects Your Loan
| Down Payment | Loan Amount | Monthly Payment | Total Interest (30yr, 6.5%) |
|---|---|---|---|
| 5% ($20,000) | $380,000 | $2,401 | $484,360 |
| 10% ($40,000) | $360,000 | $2,275 | $459,000 |
| 20% ($80,000) | $320,000 | $2,022 | $408,000 |
| 30% ($120,000) | $280,000 | $1,770 | $357,200 |
15-Year vs. 30-Year Mortgage
A 15-year mortgage typically has a lower interest rate (often 0.5–0.75% less) and you pay far less total interest. On a $320,000 loan: 30-year at 6.5% costs ~$408,000 in interest. 15-year at 6.0% costs only ~$167,000 in interest — a savings of over $240,000, though your monthly payment is significantly higher (~$2,703 vs. $2,022).
PMI — Private Mortgage Insurance
If your down payment is less than 20% of the home price, most lenders require PMI. This typically costs 0.5%–1.5% of the loan amount per year, added to your monthly payment. Once your equity reaches 20%, you can usually request PMI cancellation.
Frequently Asked Questions
A basic mortgage payment covers Principal (loan repayment) and Interest (lender charge). Your actual payment may also include Taxes (property tax) and Insurance (homeowner's + PMI), collectively known as PITI.
A common guideline is the 28/36 rule: your mortgage payment should not exceed 28% of your gross monthly income, and total debt payments should not exceed 36%. For a $6,000/month income, your max mortgage payment would be $1,680/month.
Yes. Borrowers with credit scores above 760 typically get the best rates. A 1% rate difference on a $300,000 loan saves roughly $60,000 in interest over 30 years.
Extra principal payments directly reduce your loan balance, shrinking the interest charged each subsequent month. Even one extra payment per year on a 30-year loan can cut 4–6 years off the loan term.
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