Highlight Duplicates In Google Sheets

Steps to highlight duplicates in Google Sheets

• Step 1: Select the range of cells you want to highlight.
• Step 2: Click the Format menu, then choose Conditional formatting.
• Step 3: In the Format rules section, select Custom formula is from the dropdown.
• Step 4: Enter the formula to detect duplicates
  In the input field below, type the formula:
  =COUNTIF($A$1:$A$100, A1) > 1
  (Use absolute references for the full range using F4, and a relative reference for the first cell in the range, e.g., A1.)
• Step 5: Click Done to apply the formatting.

Result: Duplicate values within the selected range will be automatically highlighted based on your conditional formatting rule.

Tip: You can change the formatting style (like background color or text color) in the sidebar to make duplicates more visible.