It counts the number of A1 values that are in column A - if there are
more than 1 this means there are duplicates. As the formula is applied
to the second row the A1 becomes A2, so it counts the number of A2
values in column A. Similarly down the column.

Hope this helps.

Pete

On Feb 2, 6:23*pm, Khoshravan
wrote:
Could you please explain what is the functionality of COUNTIF(A:A,A1)1? I
know it gives true if the numbers are repeated and give false if they are not
equal, but I can't figure out how does it work.



"Stefi" wrote:
If numbers are in column A then apply conditional formatting to column A with
this formula:

=COUNTIF(A:A,A1)1

and assign a pattern to it!

Regards,
Stefi

„john talbot” ezt írta:

I have a spreadsheet containing lists of serial numbers. If I enter a serial
number which already exists in the spreadsheet, I would like the new cell to
be highlighted to indicate that the entry already exists - is this possible?- Hide quoted text -

- Show quoted text -