i cant figure this out: I'm trying to figure out which formula would make it work. here's a simplified one i did: what i'm trying to do is find a formula that'll give me in the B Column a "TRUE" value when there are two (or more) same numbers within the column (and "FALSE" when there's only one number within the column) So this case, B4, B5, and B9 would be TRUE and the rest would be FALSE. and no, this aint homework, it is more of a work project that i'm doing...which has ~2000 (and growing) rows of data and i want to make sure that it doesnt have repeats.

I don't have the time to sit down right now and play with it (probably will in a few hours though) but have you tried playing around with the IF statements?

=COUNTIF(A:A,A1) Put that in B1 and it'll check all the values in the A column against the one in A1 and return a number indicating how many times it occurs.

You can do what RabidYak said for each row and put that in a hidden column or way far out on the spreadsheet say column J or column AA then in B1 type: =IF(J1>1, "TRUE", "FALSE") Then just select the cell and replicate the formula all the way down column B Column C below contains the number of times the value in column B ocurred using the COUNTIF statement.