Spotting Clones. How to Identify Duplicates in Google Sheets

How to Identify Duplicates in Google Sheets #

Duplicates in a Google Sheets document can often lead to errors and confusion. Whether you are managing data, tracking inventory, or collecting survey responses, it is important to identify and eliminate any duplicate entries. In this article, we will explore two methods to identify duplicates in Google Sheets: manual detection and using a Google Apps Script.

Manual Detection #

Select the Data Range: Start by selecting the range of cells where you suspect duplicates might exist. For example, if you want to check for duplicates in column A, select all the cells in that column.
Conditional Formatting: In the menu bar, click on "Format" > "Conditional Formatting". This will open the Conditional Formatting pane on the right side of the screen.
Create a New Rule: Within the Conditional Formatting pane, click on the "Add new rule" button.
Set the Rule: In the dialogue box that appears, choose "Custom formula is" from the dropdown menu. Use the following formula: =COUNTIF($A:$A, A1)>1. Replace $A:$A with the range you selected in step 1. This formula checks if a value in a cell appears more than once in the selected range.
Choose the Formatting Style: Select the formatting style you want to apply to the duplicate cells. This helps in visually identifying the duplicates. You can choose from various formatting options like bold font, highlighting, or changing the cell color.
Apply the Rule: Click on the "Done" button to apply the rule. Now, all the duplicate cells in the selected range will be highlighted based on the formatting style you chose.

By following these steps, you can manually identify duplicates in Google Sheets using conditional formatting. This method works well for small to medium-sized datasets. However, for larger datasets or if you frequently work with the same sheet, automating the process using a Google Apps Script can be more efficient.

Google Apps Script #

To use a Google Apps Script to identify duplicates, follow these steps:

Open the Script Editor: In your Google Sheets document, go to "Extensions" > "Apps Script". This will open the Google Apps Script editor in a new tab.
Write the Script: Replace the default code in the script editor with the following code snippet:

function identifyDuplicates() {
  var sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();
  var range = sheet.getDataRange();
  var values = range.getValues();
  var uniqueValues = new Set();

  for (var i = 0; i < values.length; i++) {
    for (var j = 0; j < values[i].length; j++) {
      var cellValue = values[i][j].toString();
      if (cellValue !== "") {
        if (uniqueValues.has(cellValue)) {
          sheet.getRange(i + 1, j + 1).setBackground("red");
        } else {
          uniqueValues.add(cellValue);
        }
      }
    }
  }
}

Save and Run the Script: Save the script by clicking on the floppy disk icon or by pressing "Ctrl + S" (or "Cmd + S" on Mac). Then, click on the play button to run the script.
Review the Results: The script will loop through all the cells in the active sheet and identify duplicate values. It will then highlight the duplicate cells in red. You can modify the script or formatting as per your requirements.

Use Case Examples #

Here are a few use case examples where identifying duplicates in Google Sheets can be particularly helpful:

Customer data: Maintaining a clean database of customer contact information is essential for effective marketing campaigns. Identifying and eliminating duplicate entries ensures accurate communication and avoids redundancy.
Inventory management: When managing inventory, duplicate entries can lead to ordering errors and discrepancies. By identifying duplicates, you can maintain accurate stock levels and improve efficiency.
Survey responses: If you collect survey responses in a shared Google Sheet, identifying duplicate entries helps ensure the integrity and accuracy of the data you are analyzing. It prevents the skewing of results due to repeated submissions.

In conclusion, identifying duplicates in Google Sheets is crucial for data accuracy and maintaining a clean dataset. By following the manual detection method or using a Google Apps Script, you can efficiently locate and eliminate duplicates within your spreadsheet, improving overall data integrity.

How to Highlight Duplicates: To highlight duplicates in Google Sheets, you can use conditional formatting.

How to Delete Duplicates: If you need to remove duplicate entries from your Google Sheets.

How to Find Duplicates in a Column: To identify duplicates in a specific column in Google Sheets, you can utilize the built-in functions.

How to Identify Duplicates: If you want to learn how to identify duplicates in Google Sheets as a whole.

How to Delete Empty Rows: Removing empty rows in Google Sheets can be done using different methods.

Published 20 Jul 2023