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ARM Or Fixed-Rate Calculator

Use this ARM or fixed-rate calculator to determine whether a fixed-rate mortgage or an adjustable rate mortgage (ARM), will be better for you when buying a home. The calculator also compares fully amortizing or interest-only ARMs.

To use the calculator, first enter the mortgage amount, term and rate in the boxes under “Fixed Rate Mortgage.” You can also move the little blue triangles along each dotted line. To fill in the same boxes for “Fully Amortizing ARM” and “Interest-only ARM,” click the “[+]” symbol in each category. 

Under “Report Amortization,” you can click off “annually” or “monthly.” Then click “View Report,” and scroll down to see a results summary and a breakdown of how your payments and loan balance for all the loans change each month or year.

Our calculator lets you compare options side by side – and decide whether the certainty of a fixed rate or the savings of an ARM is the right choice for you.