Select the range you want to check
Go to Home → Conditional Formatting → Highlight Cells Rules → Duplicate Values
Choose a highlight style → OK
To find duplicates only, filter afterward: select the range → Data → Filter → use the duplicate-highlighted indicator (or reapply conditional formatting to a helper column)
To remove duplicates: select the range → Data → Remove Duplicates → choose the columns → OK
To count duplicates with a formula: in a new column enter `=COUNTIF($A:$A,A2)` (adjust ranges/column as needed)
To flag duplicates with a formula: `=IF(COUNTIF($A:$A,A2)>1,”Duplicate”,”Unique”)`
To detect duplicates across multiple columns: use `=COUNTIFS($A:$A,A2,$B:$B,B2)>1` (adjust columns/ranges)
To list duplicates only: create a helper column with the flag formula, then filter for `”Duplicate”`
To use Advanced Filter: select the range → Data → Advanced → choose “Filter the list, in place” or “Copy to another location” → set “Criteria range” to a criteria table for duplicates (e.g., using a helper flag)
To check duplicates with a PivotTable: insert PivotTable → drag fields to Rows → add Values as Count → review counts greater than 1