= Excel De-duplication = <> ---- == COUNTIF == A simple way to identify duplicates is to use the [[Excel/CountIf|COUNTIF]] function. Consider the following spreadsheet: || ||'''A'''||'''B'''|| ||'''1'''||Alice ||1 || ||'''2'''||Bob ||2 || ||'''3'''||Charlie||3 || ||'''4'''||Daisy ||4 || ||'''5'''||Edward ||5 || {{{ =COUNTIF($A:$A,A1)=1 }}} Alternatively, to identify the unique cases and the first case of a duplicated set, try: {{{ =COUNTIF($A$1:A1,A1)=1 }}} Alternatively, to mark the duplicate sequence of a case, try: {{{ =IF(COUNTIF($A:$A,A1)>1,COUNTIF($A$1:A1,A1),"") }}} ---- CategoryRicottone