Google Sheets
Highlight Duplicate Column Cells In Google Sheets
Assume you have data like below and want to highlight the duplicate values: NamesLiamNoahOliverElijahHenryAlexanderOliverWilliamJamesBenjaminLucasNoah To highlight, click on "Format" and select "Conditional Formatting" Now select formatting RULE as "Custom Formula" and enter below formula. =countif(A:A,A1)>1