Looking For Online Mortgage Calculator To Compare Costs

Hello,

I am looking for a specific type of online mortgage calculator - I am looking for one that can compare the costs between 2 different mortgages. To explain, I have been provided numbers on a 30 year fixed mortgage between 2 different lenders; one has a lower rate and higher fees, and the other is a higher rate and lower fees. I recall seeing a calculator where you could enter the numbers and it would then tell you how long you would need to keep the house until the lower rate / higher fee mortgage would make more sense.

If anyone knows where to find this calculator, I would surely appreciate it.

Thanks in advance!