# How to Highlight Duplicates in Two Columns in Excel: A Step-by-Step Guide

Highlighting duplicates in two columns in Excel can be a game-changer for data management. Essentially, you’ll use Excel’s Conditional Formatting feature to quickly spot any duplicate values. Here’s a quick guide: first, select the two columns you want to compare. Then, use Conditional Formatting to highlight the duplicates. Voila! Your duplicates will be easily visible.

## Step-by-Step Tutorial: Highlight Duplicates in Two Columns in Excel

In this tutorial, we’ll walk you through how to use Excel to highlight duplicate values in two separate columns. This can be useful for data validation, analysis, or simply cleaning up your datasets.

### Step 1: Select Your Columns

First, highlight the two columns you want to compare.

You can do this by clicking and dragging over the column letters at the top. If the columns aren’t next to each other, hold down the Ctrl key while you click each column letter.

### Step 2: Open Conditional Formatting

Next, go to the Home tab and click on "Conditional Formatting."

This option is usually found in the Styles group under the Home tab. Clicking it will open a dropdown menu with various formatting options.

### Step 3: Choose New Rule

From the dropdown, select “New Rule.”

This will open a dialog box that gives you different options for applying conditional formatting rules.

### Step 4: Use a Formula to Determine Which Cells to Format

In the New Formatting Rule dialog box, select “Use a formula to determine which cells to format.”

This option allows you to input a custom formula to find duplicates in the selected columns.

### Step 5: Enter the Formula

Enter the formula `=COUNTIF(\$A\$1:\$A\$100, \$B1)` in the formula box.

Replace `\$A\$1:\$A\$100` with your actual column range. This formula checks if the value in column B exists in column A.

### Step 6: Set Your Format

Click the “Format” button to choose how you want your duplicates to be highlighted.

You can change the font color, fill color, or even add borders to make the duplicates stand out.

### Step 7: Apply the Rule

Click “OK” to apply the formatting rule.

Once you hit OK, Excel will highlight all the duplicates in your selected columns based on your specified format.

After completing these steps, your Excel sheet will automatically highlight duplicate values, making them easy to spot and manage.

## Tips for Highlighting Duplicates in Two Columns in Excel

1. Backup Your Data: Always make a backup of your data before applying any conditional formatting to avoid accidental data loss.
2. Custom Formatting: Feel free to customize the formatting to fit your needs. Bright colors like yellow or red can make duplicates stand out more.
3. Use Filters: You can combine this method with Excel’s Filter feature to quickly review the duplicates.
4. Update Ranges: Make sure to adjust the formula range if you add more data to your columns.
5. Cross-Workbook Comparisons: Consider using Excel’s VLOOKUP function for comparing columns in different workbooks.

### What if my columns are not side by side?

You can still highlight non-adjacent columns by holding down the Ctrl key while selecting each column.

### What happens if I add new data?

If you add new data, make sure to update the range in your COUNTIF formula to include the new cells.

### Can I remove the highlighting later?

Yes, you can go to Conditional Formatting > Clear Rules to remove the highlighting.

### Does this work in all versions of Excel?

This method works in most modern versions of Excel, including Excel 2010 and later.

## Summary

2. Open Conditional Formatting
3. Choose New Rule
4. Use a formula to determine which cells to format
5. Enter the formula
7. Apply the rule

## Conclusion

Highlighting duplicates in two columns in Excel is a powerful feature that can save you loads of time and effort. By following the simple steps outlined in this guide, you can easily spot and manage duplicate entries in your datasets. Whether you’re a student, a professional, or just someone who loves organizing data, mastering this skill will make you more efficient and effective.

Excel is a versatile tool, and knowing how to utilize its advanced features can elevate your data management game. If you found this helpful, consider exploring other Excel functions like VLOOKUP, PivotTables, or Data Validation. Your journey to becoming an Excel whiz doesn’t stop here. Happy Excel-ing!