Mortgage Calculator
Calculate monthly mortgage payments and total interest. Free, no signup.
How It Works
Enter your loan amount, annual interest rate, and term. The calculator uses the standard amortization formula to compute your fixed monthly payment, total interest paid, and total cost of the loan. Results update instantly as you type — there is no Calculate button to press.
The figures cover principal and interest only. Property tax, homeowners insurance, PMI, and HOA dues are separate costs that are not part of this estimate, so budget for them on top of the payment shown.
How Term and Rate Affect the Payment
A longer term lowers the monthly payment but raises total interest, while a shorter term does the opposite. A higher interest rate increases both. The table below shows the monthly principal-and-interest payment on a $300,000 loan at a few common rates and terms.
| Rate | 15-year | 30-year |
|---|---|---|
| 5.0% | $2,372 | $1,610 |
| 6.0% | $2,532 | $1,799 |
| 6.5% | $2,613 | $1,896 |
| 7.0% | $2,696 | $1,996 |
| 8.0% | $2,867 | $2,201 |
Why Use It
Compare loan scenarios before you commit, check whether a 15-year term fits your budget, or see how much a rate change adds over the life of the loan. Because it runs locally in your browser, you can run as many what-if numbers as you like privately, with nothing sent to a server.
Frequently Asked Questions
How is a monthly mortgage payment calculated?
It uses the standard amortization formula. The annual interest rate is divided by 12 to get a monthly rate, the term in years is multiplied by 12 to get the number of payments, and those feed a formula that returns a fixed monthly amount covering both principal and interest. This calculator does the math instantly as you type.
Does this calculator include property tax, insurance, and PMI?
No. It estimates principal and interest only, which is the loan repayment portion of your payment. Property tax, homeowners insurance, PMI, and HOA fees are not included, so your actual monthly housing cost will be higher.
How much interest will I pay over the life of the loan?
The Total Interest figure shows exactly that: the monthly payment multiplied by the number of payments, minus the original loan amount. On a long 30-year term, total interest can rival or exceed the amount borrowed, which is why the tool also shows Total Cost.
What loan terms and rates can I enter?
You can set any loan amount, an interest rate from 0 to 30 percent, and a term from 1 to 50 years. A 0 percent rate is handled correctly by dividing the loan evenly across the payments. Common terms are 15 and 30 years.
Is my financial information kept private?
Yes. Every calculation runs entirely in your browser using JavaScript. Nothing you type is sent to a server, stored, or shared, and no signup is required.