Identifying Duplicate Values in an Excel List
From time to time, you may need to identify duplicate values with a list in Excel. Modern versions, including Excel 2007 and later, provide this capability with just a few mouse clicks. For good measure, I'll also describe a worksheet function-based approach that works in any version of Excel.
As shown below, you can easily identify duplicate invoice numbers in a list. To do so:
- Select the range of cells you wish to test. One way to do so is to click on a single cell and then press Ctrl-A.
- On Excel's Home tab, choose Conditional Formatting, Highlight Cells Rules, and then Duplicate Values.
- Click OK within the Duplicate Values dialog box to identify the duplicate values.
- Duplicate values in the list will now be identified.
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You can then isolate just the duplicates, as shown below:
- Right-click on one of the duplicate cells, choose Filter, and then Filter by Selected Cell's Color.
- This collapses the list to show just the duplicate values, which you can copy and paste to another worksheet, or otherwise manage, as shown below.
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To remove the conditional formatting, one approach is to click the Conditional Formatting button, choose Clear Rules, and then Clear Rules from Entire Worksheet, as shown below:
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Source: David H. Ringstrom, CPA heads up Accounting Advisors, Inc., an Atlanta-based software and database consulting firm providing training and consulting services nationwide.