A mortgage payment is the single biggest check most households write every month. This calculator takes your loan amount, your interest rate, and your loan term, and returns the exact monthly principal-and-interest (P&I) payment — plus the total interest you will pay over the life of the loan and the total amount you will repay in full.
Unlike a full PITI tool, this page stays focused: it does not ask for home price, down payment percentage, property tax, insurance, PMI, or HOA. It answers one question cleanly — how much is my monthly mortgage payment? — so you can compare rate and term scenarios in seconds.
How to Use
- Enter the Loan Amount — the principal you are borrowing. If you are buying a home, this is the purchase price minus your down payment (for example, a $375,000 home with $75,000 down = a $300,000 loan). If you are refinancing, it is your current remaining balance.
- Type your Interest Rate (APR). If you have not locked a rate yet, plug in the national average for your credit profile, then test a range of ±0.5% to stress-test your budget.
- Choose the Loan Term — 10, 15, 20, or 30 years. Thirty-year loans are the most common; fifteen-year loans usually carry a lower rate and build equity much faster.
- Read the result card: Monthly Principal & Interest is the fixed payment your lender will show you on the note, Total Interest Over Life shows what the loan actually costs you beyond the principal, and Total Paid Over Life is the grand sum of every check you send across the full amortization.
The payment recalculates instantly as you move any slider. There are no hidden fields, no escrow assumptions, and no optional add-ons — just the core amortization math.
The Mortgage Payment Formula
Your monthly payment comes from the standard amortization (PMT) formula used by Fannie Mae, Freddie Mac, and every major US lender:
M = P × r(1 + r)ⁿ / ((1 + r)ⁿ − 1)
Where:
- M is the monthly payment.
- P is the loan amount (the principal you borrowed).
- r is the monthly interest rate — the annual APR divided by 12.
- n is the total number of monthly payments — the loan term in years times 12.
Worked example on a $300,000 loan at 7.0% for 30 years: the monthly rate is 0.07 / 12 = 0.005833, and n = 360. Plugging into the formula gives a monthly P&I of $1,995.91. Over 360 months you will pay 360 × $1,995.91 = $718,526.69 in total, which means the interest alone is $418,526.69 — more than the original principal. That is why even a 0.5% rate difference or a shorter term has such a large effect on your wallet.
If the interest rate is 0%, the formula divides by zero, so the engine simply splits the principal evenly across the number of months. A $200,000 interest-free loan repaid over 360 months is $555.56 per month, and the total interest is exactly $0.
How Rate and Term Move the Payment
Three knobs drive your monthly payment: principal, rate, and term.
- More principal raises the payment proportionally. Doubling the loan roughly doubles the P&I.
- Higher rate raises the payment non-linearly. On a $300,000, 30-year loan, moving from 6.0% to 8.0% lifts the monthly check from about $1,799 to about $2,201 — a $402 difference every month for the life of the loan.
- Shorter term raises the monthly payment but sharply reduces total interest. The same $300,000 loan at 7.0% is $2,696.48 per month over 15 years instead of $1,995.91 over 30, but total interest drops from $418,526.69 to $185,367.27 — a saving of roughly $233,000.
Use this calculator to flip between 15- and 30-year scenarios on your exact loan amount; the trade-off is almost always larger than people expect.
Examples
Example 1 — A typical first purchase. A household takes out a $300,000 loan at 7.0% for 30 years. The monthly principal-and-interest payment is $1,995.91. Over the full 30 years they will pay back $718,526.69, of which $418,526.69 is interest alone. (Property tax, insurance, and PMI are billed separately through escrow and are not included in this figure.)
Example 2 — Refinancing into a shorter term. A borrower currently owes $250,000 on a 30-year loan at 7.5% and refinances into a 15-year loan at 6.5%. The new monthly P&I is about $2,178 — slightly higher than their old payment — but total interest over the new loan drops to roughly $142,000, saving well over $100,000 compared with staying on the original schedule.
Example 3 — A jumbo-scale loan. On a $1,000,000 loan at 7.0% for 30 years, the monthly P&I alone is $6,653.02, and total interest over the life reaches $1,395,088.98. Running this number before you shop for a high-priced home prevents you from falling in love with a property your budget cannot actually carry.
Example 4 — A zero-rate promotional comparison. A $200,000 loan at 0% over 30 years costs $555.56 per month with $0 interest. The same $200,000 at 7.0% over 30 years costs $1,330.60 per month and $279,015 in interest. The comparison makes it obvious why a low introductory rate matters even on a modest principal.
FAQ
How is a mortgage monthly payment calculated?
The payment uses 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 (annual APR divided by 12), and n is the number of monthly payments (loan term in years times 12). This is the same formula used by Fannie Mae, Freddie Mac, and major US lenders.
What is the difference between a mortgage payment and PITI?
This calculator reports only principal and interest (P&I) — the part that pays down the loan balance and pays the lender. PITI adds property tax, home insurance, and private mortgage insurance (and sometimes HOA) on top. Your actual monthly statement will usually be higher than the P&I figure shown here because those escrow items are bundled in.
Is a 30-year or 15-year mortgage payment better?
A 15-year loan usually carries a lower rate and saves tens of thousands of dollars in interest, but the monthly payment is roughly 30–50% higher. Choose a 15-year loan if your cash flow is comfortable and you want forced savings; choose a 30-year loan if you want flexibility or plan to invest the monthly difference at a return above your mortgage rate. You can always prepay a 30-year loan as if it were a 15-year one, but you cannot stretch a 15-year loan back out.
How much should my mortgage payment be?
Lenders generally prefer your total housing cost — PITI — to stay under roughly 28% of your gross monthly income (the "front-end ratio"), and your total monthly debts including the mortgage to stay under 36–43% (the "back-end ratio"). Use the P&I figure here as the starting point, then add estimated tax, insurance, and PMI to compare against your income.
Why is my interest total so much larger than the loan itself?
At a 7.0% rate on a 30-year loan, roughly 58% of your total payments go to interest ($418k on a $300k loan). This is normal for a long-term amortizing loan: early payments are almost entirely interest, and only gradually shift toward principal over the second half of the term. A shorter term or a lower rate reduces this skew dramatically.
Does this calculator include property tax, insurance, and PMI?
No. This page is a focused P&I payment solver. If you want the full monthly housing bill including tax, insurance, PMI, and HOA, use a PITI mortgage calculator. As a rule of thumb, escrow items commonly add 20–40% on top of the P&I figure you see here.
Disclaimer
This mortgage payment calculator is provided for informational purposes only and does not constitute financial, lending, or tax advice. Estimates are based on the inputs you enter and the standard amortization formula; actual offers vary by lender, credit profile, location, and program. Property tax, insurance, PMI, and HOA figures are not included in this tool's output. Always confirm your final payment and terms directly with a licensed mortgage professional before committing to a loan.