Create a Formula-type
field with this formula:
LEN(CONCATENATE({Field 1},{Field 2},{Field 3},{Field 4},{Field 5}))/4
^ The formula is combining all the values of the fields into one long string. If a Checkbox
-type field is checked, its value is true
. So you want the length of the combined string divided by 4.
Or just use COUNTALL()
COUNTALL({Field 1},{Field 2},{Field 3},{Field 4},{Field 5})