Mortgage Calculator
Calculate your monthly mortgage payment, total interest, and view a detailed amortization schedule.
By Evan Carter · Updated August 15, 2026
Monthly Payment
$1,770
Principal & interest only
| Year | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| 1 | $21,237 | $3,130 | $18,108 | $276,870 |
| 2 | $21,237 | $3,339 | $17,898 | $273,531 |
| 3 | $21,237 | $3,563 | $17,675 | $269,968 |
| 4 | $21,237 | $3,801 | $17,436 | $266,167 |
| 5 | $21,237 | $4,056 | $17,181 | $262,111 |
What Is Inside a Mortgage Payment
A mortgage is a long-term loan secured by the home you are buying. Each monthly payment is split between principal (the portion that reduces your outstanding loan balance) and interest (the cost the lender charges for borrowing the money). This calculator computes the fixed principal-and-interest payment for a standard fixed-rate mortgage and then maps out exactly how that payment is applied over every month and year of the loan.
The math behind it is the standard amortization formula: M = P[r(1+r)^n] / [(1+r)^n − 1]. Here P is the loan amount (home price minus down payment), r is the monthly interest rate (the annual rate divided by 12), and n is the total number of monthly payments (years multiplied by 12). The formula solves for the constant payment M that pays the loan down to exactly zero by the final month.
Example: A $300,000 Home with 20% Down
Suppose you buy a home priced at $300,000 and put 20% down, leaving a loan of $240,000. At a hypothetical 6% annual rate over 30 years, the monthly rate is 0.5% (0.06 ÷ 12) and there are 360 payments. Plugging these into the formula produces a principal-and-interest payment of roughly $1,439 per month. In the very first payment, about $1,200 goes to interest and only around $239 to principal. By the final years that ratio flips, with almost the entire payment reducing your balance. Try entering these numbers above to watch the breakdown update in real time.
Factors That Affect Your Payment
Your monthly mortgage payment depends on four key inputs. Adjusting any one of them changes both your payment and the total interest you pay:
- Home price: A higher price means a larger loan and a higher payment, assuming the same down payment percentage.
- Down payment: A bigger down payment shrinks the loan amount, lowers the payment, and can help you avoid private mortgage insurance.
- Interest rate: Even a small rate change has an outsized effect over 30 years. Shopping multiple lenders is one of the highest-value steps you can take.
- Loan term: A longer term lowers the monthly payment but increases the total interest paid; a shorter term does the reverse.
Interpreting the Results and Common Mistakes
The single most useful number to watch is total interest paid, shown alongside your monthly payment. It reveals the true lifetime cost of the loan, which is often a striking share of the amount borrowed. A frequent mistake is shopping only by monthly payment: stretching to a longer term can make a payment look affordable while quietly adding tens of thousands of dollars in interest. Another common oversight is forgetting that this figure covers principal and interest only. Property taxes, homeowners insurance, PMI, and any HOA dues are billed on top and should be part of your real housing budget.
How to Lower Your Mortgage Payment
Several strategies can reduce your monthly payment, each with a trade-off. Increasing your down payment or choosing a less expensive home directly shrinks the loan. Securing a lower interest rate through rate shopping or by paying discount points reduces the cost of borrowing. Extending the loan term lowers the monthly payment but raises total interest, so weigh short-term cash flow against long-term cost. Making extra principal payments later on can also shorten the loan dramatically.
Building Equity Over Time
Equity is the share of the home you actually own, equal to its value minus your remaining loan balance. It grows two ways: as you pay down principal and as the property potentially appreciates. Because early payments are mostly interest, equity from principal builds slowly at first and accelerates in the later years of the loan, which the amortization schedule below makes clear. Reaching roughly 20% equity is a common milestone, since it is the point at which private mortgage insurance can typically be removed, lowering your overall housing cost.
Many lenders also collect property taxes and homeowners insurance through an escrow account, adding those amounts to your monthly bill and paying them on your behalf when due. That is why your actual payment to the lender is often noticeably higher than the principal-and-interest figure this calculator shows. Knowing the difference helps you budget for the true monthly cost of owning the home rather than just servicing the loan.
Where the Other Loan Calculators Fit
Use this mortgage calculator for home purchases and refinances on fixed-rate loans. If you want to study how additional principal payments accelerate payoff, the amortization calculator lets you add an extra monthly amount. For a car purchase, the auto loan calculator factors in trade-in value and sales tax, and for general installment debt the loan calculator handles any fixed-rate balance.
Frequently Asked Questions
How is my monthly mortgage payment calculated?
Your monthly payment is calculated using the standard amortization formula: M = P[r(1+r)^n]/[(1+r)^n-1], where P is the loan amount, r is the monthly interest rate, and n is the total number of monthly payments. This gives you a fixed payment that covers both principal and interest over the life of the loan.
How much should I put down on a house?
A 20% down payment is traditionally recommended because it lets you avoid private mortgage insurance (PMI). However, many loan programs accept as little as 3-5% down. A larger down payment reduces your monthly payment and total interest paid, but you should also keep enough savings for emergencies and closing costs.
What is the difference between a 15-year and 30-year mortgage?
A 15-year mortgage has higher monthly payments but a lower interest rate, and you pay significantly less total interest. A 30-year mortgage has lower monthly payments, giving you more cash flow flexibility, but you pay more interest over the life of the loan. Use this calculator to compare both options.
Does this calculator include property taxes and insurance?
This calculator shows principal and interest only. Your actual monthly housing cost will also include property taxes, homeowners insurance, and potentially PMI and HOA fees. These additional costs can add several hundred dollars per month depending on your location, so budget for the full PITI (principal, interest, taxes, insurance) figure rather than principal and interest alone.
What is PMI and how do I get rid of it?
Private mortgage insurance protects the lender if you default, and it is typically required when your down payment is under 20%. It is added to your monthly payment as a separate line item. Once your loan balance falls to about 80% of the home's value, you can usually request that PMI be canceled, and it often drops off automatically at 78%.
Should I pay discount points to lower my rate?
A discount point is an upfront fee equal to 1% of the loan amount that buys a lower interest rate. Points make sense if you plan to keep the loan long enough to recoup the cost through monthly savings. To find the break-even point, divide what you pay in points by your monthly savings. If you may sell or refinance before then, paying points usually is not worth it.
How much house can I afford?
A common guideline is the 28/36 rule: keep your total housing payment at or below 28% of gross monthly income, and all debt payments at or below 36%. Lenders also weigh your credit score, down payment, and existing debts. This calculator helps you test different home prices so you can find a monthly payment that fits comfortably within your budget.
Does this calculator account for refinancing?
Not directly, but you can model a refinance by entering your current loan balance as the home price, setting the down payment to zero, and using the new rate and term you are considering. Compare the resulting payment and total interest against your existing loan to decide whether refinancing and any associated closing costs make sense for you.
This calculator provides estimates for informational purposes only. Results should not be considered as financial advice. Actual amounts may vary based on additional factors not included in this calculator. Consult a qualified financial advisor for personalized advice.
Tax data is based on 2026 federal and state rates (IRS Rev. Proc. 2025-32, Tax Foundation). State bracket thresholds may differ slightly from official figures due to rounding and inflation adjustments. Data is updated annually and may not reflect mid-year legislative changes.
See how we calculate and our editorial policy for the formulas, sources, and review process behind this tool.