To find duplicate rows in Excel, follow these steps:
1. Select the range of data you want to check for duplicates.
2. Go to the Home tab, click Conditional Formatting, and choose Highlight Cells Rules > Duplicate Values.
3. In the dialog box, select a format for highlighting duplicates and click OK.
4. Excel will highlight all duplicate rows based on the selected columns.
For advanced cases, you can use the COUNTIF function to flag duplicates in a helper column or apply the Remove Duplicates tool under the Data tab to eliminate or analyze them.