Try this:

=SUMPRODUCT((A1:A10=6)/COUNTIF(B1:B10,B1:B10&""))


"Bigfoot17" wrote:

I am trying to count the unique numbers in COlumn B where the value in Column
A=6. I have figured out how to find the number of unique values in all of
Column B but not where the value in Column A=6. Any suggestions appreciated.

=SUM(IF(FREQUENCY(Log!$B$1:$B$25,Log!$B$1:$B$25)0 ,1))


(A) (B) (C)
5 001
5 002
5 002
5 003
6 004
6 005
6 005
7
7 006
8 007