ECTS credits for US teaching credentials
depending what country in EU ( Usually it is few differences in hours ) 60 points ( credits by US systems ) is equivalent to 25-30 hours per credit ( point ) 
It would be helpful if you can clarify what is 12 graduate hours.


The rough equivalent of 5 ECTS credits is 2.5 American credits, 
Therefore we advise to transfer credits along this 2:1 ratio. 
Students from universities with an American credits system should verify their school's credit-granting process. 
Transfer of credits is at the discretion of the home institution.


This is something that is usually mentioned across internet. 
However according to this source `A standard full-time study load is usually 30 credit hours per year. Typically, in order to graduate with a degree, universities expect students to complete:

120-130 credit hours for a Bachelor’s degree

so 1.67 ECTS = 1.00 US College Credit Hours

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