In this tutorial, you will learn how to automatically highlight duplicates in Excel once something has been typed. We are going to have a close look at how to shade duplicate cells, entire rows, or consecutive dupes using conditional formatting and a special tool.
Last week, we explored different ways to identify duplicates in Excel with formulas. Undoubtedly, those solutions are very useful, but highlighting duplicate entries in a certain color could make data analysis even easier.
The fastest way to find and highlight duplicates in Excel is using conditional formatting. The biggest advantage of this method is that it not only shows dupes in the existing data but automatically checks new data for duplicates right when you enter it in a worksheet.
These techniques work in all versions of Excel 365, Excel 2021, Excel 2019, Excel 2016, Excel 2013, Excel 2010 and lower.
How to highlight duplicates in Excel
In all Excel versions, there is a predefined rule for highlighting duplicate cells. To apply this rule in your worksheets, perform the following steps:
- Select the data you want to check for duplicates. This can be a column, a row or a range of cells.
- On the Home tab, in the Styles group, click Conditional Formatting > Highlight Cells Rules > Duplicate Values…
- The Duplicate Values dialog window will open with the Light Red Fill and Dark Red Text format selected by default. To apply the default format, simply click OK.
Apart from the red fill and text formatting, a handful of other predefined formats are available in the dropdown list. To shade duplicates using some other color, click Custom Format… (the last item in the drop-down) and select the fill and/or font color of your liking.
Tip. To highlight unique values, select Unique in the left-hand box.
Using the inbuilt rule, you can highlight duplicates in one column or in several columns as shown in the following screenshot:
Note. When applying the built-in duplicate rule to two or more columns, Excel does not compare the values in those columns, it simply highlights all duplicate instances in the range. If you want to find and highlight matches and differences between 2 columns, follow the examples in the above linked tutorial.
When using Excel's inbuilt rule for highlighting duplicate values, please keep in mind the following two things:
- It works only for individual cells. To highlight duplicate rows, you would need to create your own rules either based on values in a specific column or by comparing values in several columns.
- It shades duplicate cells including their first occurrences. To highlight all duplicates except first instances, create a conditional formatting rule based on formula as explained in the next example.
How to highlight duplicates without 1st occurrences
To highlight 2nd and all subsequent duplicate occurrences, select the cells you want to color, and create a formula-based rule in this way:
- On the Home tab, in the Styles group, click Conditional Formatting > New rule > Use a formula to determine which cells to format.
- In the Format values where this formula is true box, enter a formula similar to this:
Where A2 is the top-most cell of the selected range.
- Click the Format… button and select the fill and/or font color you want.
- Finally, click OK to save and apply the rule.
If you don't have much experience with Excel conditional formatting, you will find the detailed steps to create a formula-based rule in the following tutorial: Excel conditional formatting based on another cell value.
As the result, the duplicate cells excluding first instances will get highlighted with the color of your choosing:
How to show 3rd, 4th and all subsequent duplicate records
To view duplicates beginning with the Nth occurrence, create a conditional formatting rule based on the formula like in the previous example, with the only difference that you replace >1 at the end of the formula with the required number. For example:
To highlight 3rd and all subsequent duplicate instances, create a conditional formatting rule based on this formula:
To shade4th and all subsequent duplicate records, use this formula:
To highlight only specific occurrences, use the equal to operator (=). For example, to highlight only 2nd instances, you would go with this formula:
How to highlight duplicates in a range (multiple columns)
When you want to check for duplicates over multiple columns, not by comparing the columns to each other, but find all instances of the same item in all the columns, use one of the following solutions.
Highlight duplicates in multiple columns including 1st occurrences
If the first instance of an item that appears in the data set more than once is deemed a duplicate, the easiest way to go is use Excel's built-in rule for duplicates.
Or, create a conditional formatting rule with this formula:
For example, to highlight duplicates in the range A2:C8, the formula goes as follows:
Please notice the use of absolute cell references for the range ($A$2:$C$8), and relative references for the top cell (A2).
Highlight duplicates in multiple columns except 1st occurrences
The solution for this scenario is a lot trickier, no wonder Excel has no built-in rule for it :)
To highlight duplicate entries in several columns ignoring the 1st occurrences, you will have to create 2 rules with the following formulas:
Rule 1. Applies to the first column
Here you use exactly the same formula as we used to highlight duplicates without 1st occurrences in one column (the detailed steps can be found here).
In this example, we are creating a rule for A2:A8 with this formula:
As the result, the duplicate items without 1st occurrences are highlighted in the left-most column of the range (there is only one such item in our case):
Rule 2. Applies to all subsequent columns
To highlight duplicates in the remaining columns (B2:C8), use this formula:
In the above formula, the first COUNTIF function counts the occurrences of a given item in the first column, and the second COUNTIF does the same for all subsequent columns. And then, you add up those numbers and check if the sum is greater than 1.
As the result, all duplicated items excluding their 1st occurrences are found and highlighted:
Highlight duplicates in all columns with a single rule
Another possible solution is to add an empty column to the left of your dataset, and combine the above formulas into a single formula like this:
=IF(COLUMNS($B2:B2)>1,COUNTIF(A$2:$B$8,B2),0) + COUNTIF(B$2:B2,B2)>1
Where B2 is the top cell with data in the 2nd column of the target range.
To better understand the formula, let's break it down into 2 main parts:
- For the first column (B), the IF condition is never met, so only the second COUNTIF function is calculated (we have used this formula to find duplicates except first occurrences in one column).
- For all subsequent columns (C2:D8), the key point is the clever use of absolute and relative references in the two COUNTIF functions. To make things easier to understand, I've copied it to column G, so you can see how the formula changes when applied to other cells:
Because the IF condition is always TRUE for all the columns other than the first one (number of columns is greater than 1), the formula proceeds in this way:
- Counts the number of occurrences of a given item (D5 in the screenshot above) in all columns to the left of the given column:
- Counts the number of a given item's occurrences in the item's column, up to the item's cell:
- Finally, the formula adds the results of both COUNTIF functions. If the total number is greater than 1, i.e. if there is more than one occurrence of the item, the rule is applied and the item is highlighted.
Highlighting entire rows based on duplicate values in one column
If your table contains several columns, you may want to highlight whole rows based on duplicate records in a specific column.
As you already know, Excel's built-in rule for duplicates works only at the cell level. But a custom formula-based rule has no problem with shading rows. The key point is to select the whole rows, and then create a rule with one of the following formulas:
- To highlight duplicate rows excluding 1st occurrences:
- To highlight duplicate rows including 1st occurrences:
Where A2 is the first cell and A15 is the last used cell in the column that you want to check for duplicates. As you see, the clever use of absolute and relative cell references is what makes a difference.
The following screenshot demonstrates both rules in action:
How to highlight duplicate rows in Excel
The previous example has demonstrated how to color entire rows based on duplicate values in a specific column. But what if you want to view rows that have identical values in several columns? Or, how do you highlight absolute duplicate rows, the ones that have completely equal values in all columns?
For this, employ the COUNTIFS function that allows comparing cells by multiple criteria. For example, to highlight duplicate rows that have identical values in columns A and B, use one of the following formulas:
- To highlight duplicate rows except 1st occurrences:
=COUNTIFS($A$2:$A2, $A2, $B$2:$B2, $B2)>1
- To highlight duplicate rows with 1st occurrences:
=COUNTIFS($A$2:$A$15, $A2, $B$2:$B$15, $B2)>1
The following screenshot demonstrates the result:
As you understand, the above example is for demonstration purposes only. When highlighting duplicate rows in your real-life sheets, you are naturally not limited to comparing values only in 2 columns, the COUNTIFS function can process up to 127 range/criteria pairs.
Highlighting consecutive duplicate cells in Excel
Sometimes, you may not need to highlight all duplicates in a column but rather show only consecutive duplicate cells, i.e. the ones that are next to each other. To do this, select the cells with data (not including the column header) and create a conditional formatting rule with one of the following formulas:
- To highlight consecutive duplicates without 1st occurrences:
- To highlight consecutive duplicates with 1st occurrences:
The following screenshot demonstrates highlighting consecutive duplicate texts, but these rules will also work for consecutive duplicate numbers and dates:
If your Excel sheet may have empty rows and you don't want the consecutive blank cells to get highlighted, make the following improvements to the formulas:
- To highlight consecutive duplicate cells without 1st occurrences and ignore blank cells:
- To highlight consecutive duplicate cells with 1st occurrences and ignore blank cells:
=AND($A2<>"", OR($A1=$A2, $A2=$A3))
As you see, it's no big deal to highlight duplicates in Excel using conditional formatting. However, there is even a faster and easier way. To find it out, read the next section of this tutorial.
How to highlight duplicates in Excel with Duplicate Remover
The Duplicate Remover add-in is the all-in-one solution to deal with duplicate records in Excel. It can find, highlight, select, copy or move duplicated cells or entire duplicate rows.
Despite its name, the add-in can quickly highlight duplicates in different colors without deleting them.
The Duplicate Remover adds 3 new features to your Excel Ribbon:
- Dedupe Table - to immediately find and highlight duplicates in one table.
- Duplicate Remover - step-by-step wizard with advanced options to identify and highlight duplicates or unique values in 1 table.
- Compare 2 Tables - find and highlight duplicates by comparing two columns or two separate tables.
After installing Ultimate Suite for Excel, you will find these tools on the Ablebits Data tab in the Dedupe group:
Highlighting duplicates in Excel in a couple of clicks
For this example, I've created the following table with a few hundred rows. And our aim is to highlight duplicate rows that have equal values in all three columns:
Believe it or not, you can get the desired result with just 2 mouse clicks :)
- With any cell in your table selected, click the Dedupe Table button, and the clever add-in will pick up the whole table.
- The Dedupe Table dialog window will open with all the columns selected automatically, and the Color duplicates option chosen by default. So, all you have to do is click OK :) Done!
Tip. If you want to detect duplicate rows by one or more columns, uncheck all irrelevant columns and leave only the key column(s) selected.
And the result would look similar to this:
As you see in the above image, the Dupe Table tool has highlighted duplicate rows without first instances.
If you want to highlight duplicates including first occurrences, or if you want to color unique records rather than dupes, or if you don't like the default red color, then use the Duplicate Remover wizard that has all these features and a lot of more.
Highlight duplicates in Excel using an advanced step-by-step wizard
Compared to the swift Dedupe Table tool, the Duplicate Remover wizard requires a few more clicks, but it makes up for this with a number of additional options. Let me show it to you in action:
- Select any cell within your table where you want to highlight duplicates, and click the Duplicate Remover button on the ribbon. The wizard will run and the entire table will get selected. The add-in will also suggest creating a backup copy of your table, just in case. If you don't need it, uncheck that box.
Verify that the table has been selected correctly and click Next.
- Select one of the following data types that you want to find:
- Duplicates except 1st occurrences
- Duplicates with 1st occurrences
- Unique values
- Unique values and 1st duplicate occurrences
For this example, let's find Duplicates + 1st occurrences:
- Now, select the columns to check for duplicates. Because we want to highlight complete duplicate rows, I've selected all 3 columns.
Additionally, the add-in lets you specify if your table has headers and if you want to skip empty cells. Both options are selected by default.
- Finally, choose the action to perform on duplicates. You have a number of options such as selecting, deleting, copying, moving duplicates or adding a status column to identify the dupes.
Since today we are exploring different ways to highlight duplicates in Excel, our choice is obvious :) So, select Fill with color and choose one of the standard theme colors, or click More Colors… and pick any custom RGB or HSL color.
Click the Finish button and enjoy the result :)
This is how you highlight duplicates in Excel using our Duplicate Remover add-in. If you are curious to try this tool on your own worksheets, you are most welcome to download a fully-functional trial version of the Ultimate Suite that includes all our time-saving tools for Excel. And your feedback in comments will be greatly appreciated!