One way (array-entered: CTRL-SHIFT-ENTER or CMD-RETURN):

=COUNT(MATCH(ROW(INDIRECT("1:6")),A2:F2,0))=6

In article ,
nospaminlich wrote:

I'm trying to create a formula which checks that a range of cells e.g. A2:F2
contain all the values 1,2,3,4,5,6 irrespective of which cell each number is
in.

Unfortunately, everything I've tried has failed so any help would be
appreciated.