How to Check for Duplicates in Google Sheets


Sanskar Tiwari

Google Sheets is an incredibly powerful tool for data management and analysis, used by millions to organize, manipulate, and visualize data. One common issue users encounter is the presence of duplicate data, which can skew analysis and lead to inaccurate results. In this blog post, we'll explore several methods to identify and manage duplicates in Google Sheets. We'll also touch on how can streamline these processes, enhancing your data management practices without being overly promotional.

Why Worry About Duplicates?

Duplicates can occur for various reasons, such as data entry errors, merging data from multiple sources, or simply by mistake. Regardless of the cause, duplicates can:
  • Affect data integrity and accuracy.
  • Lead to misleading analysis outcomes.
  • Increase storage usage unnecessarily.
  • Complicate data management tasks.
Identifying and removing duplicates is crucial for maintaining the reliability of your data analysis.

Method 1: Using Conditional Formatting

Conditional Formatting is a straightforward method to visually highlight duplicate data in Google Sheets. Here’s how you can use it:
  1. Select the Range: Click and drag to select the column or range of cells where you want to check for duplicates.
  1. Open Conditional Formatting: Go to Format in the menu and select Conditional formatting.
  1. Set the Format Rules:
      • Under the "Format cells if" drop-down menu, select Custom formula is.
      • Enter the formula =COUNTIF(A:A, A1)>1 (change 'A' and 'A1' to match your selected range).
  1. Choose a Formatting Style: Select a color to highlight the duplicates and click Done.
This method will highlight all duplicate values in the selected range, making it easy to visually inspect and address them.

Method 2: Using Google Sheets Functions

For those who need a more hands-on approach, using built-in functions like UNIQUE and COUNTIF can help identify duplicates.


The UNIQUE function can be used to return only the unique values from a range:
plaintextCopy code =UNIQUE(A1:A10)
This formula will display all unique entries from the range A1 to A10, allowing you to compare against the original list.


To find exact counts of each entry in a range, use:
plaintextCopy code =COUNTIF(A1:A10, "Specific Entry")
This will count how many times "Specific Entry" appears in the range A1 to A10. Adjust the range and criteria according to your data.

Method 3: Using Google Apps Script

For those with a bit of coding knowledge, Google Apps Script offers a customizable way to handle duplicates. Here’s a simple script to highlight duplicates:
javascriptCopy code function removeDuplicates() { var sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet(); var data = sheet.getDataRange().getValues(); var newData = []; for(var i in data){ var row = data[i]; var duplicate = false; for(var j in newData){ if(row.join() == newData[j].join()){ duplicate = true; } } if(!duplicate){ newData.push(row); } else { sheet.getRange(parseInt(i)+1, 1, 1, row.length).setBackground('red'); } } }
This script checks each row against previously encountered rows and highlights any duplicates in red.

Enhancing Data Management with

While Google Sheets provides robust tools for managing duplicates, integrating a tool like can further enhance your data management capabilities. offers advanced features for detecting duplicates, even in large datasets, and provides options for automatic removal or merging of duplicate entries. This can save time and reduce errors, particularly in complex sheets. also supports integration with other platforms, making it an excellent choice for teams needing comprehensive data management solutions across various software ecosystems.


Checking for duplicates in Google Sheets is essential for anyone looking to maintain accurate and reliable data. Whether you choose to use conditional formatting, built-in functions, or Google Apps Script, these tools can help you identify and manage duplicates effectively. For those looking for an even more streamlined experience, can be a valuable addition to your data management toolkit, offering specialized features that enhance productivity and data integrity.
By keeping your approach detailed yet non-promotional, this guide ensures you can manage your data in Google Sheets effectively, with providing a helpful boost when needed.