Sena, Try this

=SUM(1/COUNTIF(A1:A10,A1:A10))

Adjust to the size of your range then enter it with Ctrl+Shift+Enter

Mike

"Sena" wrote:

I have a list of codes in a column, each code will be appearing many times. I
need to count the number of codes - how do I do it.

eg:
A100
B100
A100
A100
B100

Number of codes in the above list are 2.

Thanks
--
Cheers !