What’s behind the numbers in our mortgage amortization calculator
An amortization calculator enables you to take a snapshot of the interest and principal (the debt) paid in any month of the loan.
“Amortization” is a word for the way debt is repaid in a mortgage, where each monthly payment is the same (excluding taxes and insurance). In the beginning years, most of each payment goes toward interest and only a little goes to debt reduction. That ratio gradually changes, and it flips in the later years of the mortgage. This is amortization at work.
For example, if you get a $200,000 mortgage for 30 years with an interest rate of 4.25%, your monthly principal and interest payments will be $984:
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With the first payment, $276 will go to principal (reducing the debt) and $708 will go to interest.
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Fast-forward 10 years to the 120th payment and the payment is still $984, but $420 goes to principal and $564 goes to interest.
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In the next-to-last payment, $977 goes to principal and $7 goes to interest.
What the mortgage amortization calculator does
Before you get a mortgage, you might want to know how much interest you will pay in total. If you already have a mortgage, you might want to know how much debt you’ve paid off and how much remains. Or you might want to compare different loan terms before refinancing. NerdWallet’s mortgage amortization schedule calculator can help you do all of those things. It allows you to figure out:
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How much a particular month’s house payment goes toward principal and how much goes toward interest. This information is viewed on an “amortization schedule” — a table that breaks down each payment month by month.
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How much interest you will pay over the life of the loan.
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In any given month, how much you still owe.
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How different terms, like a 30-year versus a 15-year, compare in monthly payments and interest paid over the life of the loan.
How to use our mortgage amortization calculator
To get the most out of the mortgage amortization calculator, you can personalize it with your own numbers. Fill in the data fields to the right of the graph.
The data fields contain the following inputs:
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The value or price of the home.
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The mortgage interest rate.
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The down payment (or, in the case of a refinance, the value of the home’s equity).
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The loan’s term, from one to 30 years.
The calculator has four tabs:
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“Amortization schedule” has the graph. Move the vertical slider to see how much you still owe and how much principal and interest you have paid at the end of each 12-month period.
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“Breakdown” shows, month by month, the remaining loan balance after that payment has been made. On computers and tablets, it also displays a mortgage amortization table detailing the principal and interest paid each month.
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“Monthly payment” shows the estimated monthly payment, including principal and interest, property taxes and homeowners insurance.
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“Compare loan types” gives a side-by-side view of the monthly payments and total interest paid for three loans. From left to right, they are the mortgage whose interest rate and term you specified, and a 15-year and 30-year loan at today’s mortgage rates.
