This free online Refinance Auto Loan Calculator will calculate the monthly payment and interest cost comparison between your current car loan and a new refinance loan.
Plus, unlike most other auto finance calculators, the refinance auto loan calculator also gives you the option of increasing the size of the refinance balance to include an amount of cash you think you might need  though I personally would only recommend doing so if you will use the cash to pay down higher interest rate debt.
Throughout my career of building online calculators I have continually encountered mortgage, student loan, and auto refinance calculators that use the term "monthly savings" when referring to a lower monthly payment. In my opinion this is false advertising, because in many instances the lower monthly payment will only serve to increase the cost of the existing loan.
How can that be? Well, if the smaller payment must be made for a longer period of time (higher number of payments), then the total of all lower payments can be more than the total of the smaller number of higher payments.
The only way to tell whether or not refinancing will actually save you any money is to calculate the total interest cost for both the before and the after. If the total interest cost for the refinanced car loan is less than the total interest cost for the existing loan, then yes, refinancing will save you money.
Otherwise, if the total interest cost after refinancing is greater than the total interest cost of the existing note, then no matter how low the payment is, refinancing is not saving you money ... it's costing you money.
Please keep this in mind when using any refinance calculators that are not located on freeonlinecalculatoruse.com. I will never use the word "savings" unless actual savings have been calculated to exist.
With that, let's use the Refinance Auto Loan Calculator to calculate the monthly payment and interest cost comparison between your existing car note and the refinanced car note.

Follow me on any of the social media sites below and be among the first to get a sneak peek at the newest and coolest calculators that are being added or updated each month.
Monthly What's New Email Update!
Who knows if I will show up in your next search. This will insure you'll always know what I've been up to and where you can find me! 
Online Pocket Calc  

