Hi All,

Here is an Array formula to count unique values from a filtered range(C2:C100).

=SUM(IF(FREQUENCY(IF(SUBTOTAL(3, OFFSET(C2:C100,ROW(C2:C100)-ROW(C2),0,1)),IF(LEN(C2:C100),MATCH(C2:C100,C2:C10 0,0))),ROW(C2:C100)-ROW(C2)+1)>0,1))

This must be confirmed with CTRL + SHIFT + ENTER