Calculator inputs
Compare an adjustable-rate mortgage estimate with a fixed-rate mortgage estimate.
Enter the amount in the currency you are using. Keep the same currency across money fields.
Enter the fixed annual percentage rate, not a decimal. For example, enter 6.5 for 6.5%.
Enter the adjustable-rate mortgage starting percentage, not a decimal. For example, enter 5.8 for 5.8%.
Enter the length of the period using the unit shown in the label.
Controls rounding in the displayed result only; it does not change the underlying calculation.
How this calculator works
This calculator compares starting payments only; it does not predict future ARM rate changes.
Use this result as a planning estimate. Real lending, payroll, tax, health or construction outcomes can vary based on official rules, local costs and personal circumstances.
Formula
Worked example
An ARM may start lower than a fixed rate, but future adjustments can change the real long-term cost.
Frequently asked questions
Why use this calculator?
It gives a fast estimate and helps compare related scenarios before moving to more detailed planning.
Is the result exact?
No. Treat it as a practical estimate and verify important numbers with official sources or qualified professionals.