detecting duplicate numbers

Hi,
I have a column of 1000 numbers, they should all be different, but is there a simple formula to check for any duplicates, please.

Originally Posted by robert111

Hi,
I have a column of 1000 numbers, they should all be different, but is there a simple formula to check for any duplicates, please.

The easy way might be to select the column, then Data, Filter, Advanced, Copy to another location (a new row or sheet) Unique records only

and see how many appear compared to how many you started with.
hth
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