Need help with multiple COUNTIF functions

[eugenoel]

I have 2 columns of numbers. I want to count number of cells in Column B that are different from Column A, i.e. =Countif(B1,"<>"&A1).
How can I do this without using adding 125 countif formulas (I have 125 rows)? I also have the B cells conditionally formatted if <> A1 but I cannot find how to use this condition in a formula. I hope someone can help me.

[Jonmo1]

Try

=SUMPRODUCT(--(A1:A125<>B1:B125))

[eugenoel]

Try

=SUMPRODUCT(--(A1:A125<>B1:B125))

Thanks so much! It worked

[garfield101]

Can also try
{=SUM(IF(COUNTIF(A1:A10,B1:B12)<1,1,0))}
if different nos of rows in 2 columns