Buying your first home
Work out the monthly payment before you sign, and check it fits your budget.
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Enter the amount, interest rate, and term to instantly get your monthly payment, total interest, and the full amortization schedule — plus a chart showing how your debt goes down over time.
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Scenario A
Monthly payment
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Total interest
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Total paid
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Scenario B
Monthly payment
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Total interest
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Total paid
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Remaining balance month by month for the life of the loan.
Month-by-month breakdown of principal and interest, grouped by year.
How it works
Loan amount, annual interest rate, term in years, and an optional down payment.
Monthly payment, total interest, and the full month-by-month amortization schedule.
Two banks, or the same loan over different terms. See at a glance which one saves you more.
Use cases
Work out the monthly payment before you sign, and check it fits your budget.
Compare your current mortgage against a new offer and see if switching is worth it.
Enter each bank's interest rate and see side by side which one costs less overall.
Simulate the same amount over 20 and 30 years and compare monthly payment against total interest.
The same fixed-payment formula works for any installment loan, not just mortgages.
Try different down payments and see how your monthly payment and total interest change.
Frequently asked questions
This calculator uses the amortizing (fixed-payment) system, the most common for mortgages and installment loans: the monthly payment stays the same for the life of the loan, but the portion that goes to interest goes down over time while the portion that goes to principal goes up. The formula is payment = P × r / (1 − (1 + r)⁻ⁿ), where P is the outstanding principal, r is the monthly interest rate, and n is the total number of payments.
It's the month-by-month breakdown of every payment: how much goes toward interest and how much reduces the outstanding principal, plus the balance still owed after each payment. It lets you see exactly when you start paying down more principal than interest.
No. The nominal (or note) rate is the interest rate used to calculate the payment, and it's the number you should enter here. The APR also factors in fees and other loan costs, so it's usually a bit higher than the nominal rate. To compare offers fairly, check both figures, not just the nominal rate.
The down payment is subtracted from the loan amount before the payment is calculated. The larger it is, the less principal you finance — which means a lower monthly payment and less total interest paid over the life of the loan.
It depends on your priority. A longer term means a lower monthly payment, but more total interest paid, because the lender charges interest for longer. A shorter term raises the payment but lowers the total cost of the loan. Use the two-scenario comparison to see it with your own numbers.
Yes. The fixed-payment amortization system is used for mortgages as well as personal, auto, and other installment loans. Just enter the amount, interest rate, and term of your loan.
No. The results are an informational estimate based on the numbers you enter. A real bank offer may include fees, bundled insurance, discounts, or other costs not reflected here. Always check your lender's official loan estimate or disclosure documents before deciding.
Turn on "Compare with another scenario," enter the amount, interest rate, and term for each offer, and the calculator will show you side by side the monthly payment, the total interest of each, and how much you'd save by picking the cheaper one.