Tom’s Tutorials For Excel: Conditional Formatting examples for repeated items in a list.
The Conditional formatting rule for unique entries in range A3:A14 is
=COUNTIF($A$3:$A$14,A3)=1
The Conditional formatting rule for non-unique entries in range B3:B14 is
=COUNTIF($B$3:$B$14,B3)1
The Conditional formatting rule for repeated entries in range C3:C14 is
=COUNTIF($C$3:C3,C3)1
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