Support

Support –

Logik: Highlight Duplicates

Overview

Logik: Highlight Duplicates is a simple Google Sheets™ tool that helps you quickly spot duplicate entries in your spreadsheets. It’s built for workflows like giveaway sign-ups, mailing lists, and any sheet where duplicate emails or IDs can cause problems.

With a single command, the tool:

  1. Scans a selected column (for example, Email).

  2. Applies a conditional formatting rule that highlights all rows containing duplicated values.

  3. Updates automatically as your sheet changes—new duplicates are highlighted without running the tool again.

How to Install

  1. Open Google Sheets™.

  2. Go to Extensions → Add-ons → Get add-ons.

  3. Search for “Logik: Highlight Duplicates”.

  4. Click Install and follow the authorization prompts.

How to Use

  1. Open the sheet you want to check.

  2. Ensure your header row clearly labels the column you want to analyze (for example, “Email”).

  3. Go to Extensions → Logik: Highlight Duplicates → Highlight Emails (or your chosen menu entry).

  4. The tool will:

    • Locate the email column by its header,

    • Add or update a conditional formatting rule, and

    • Highlight all duplicate rows in that column.

If you receive an error like “Could not find column with header …”, double-check your header row spelling and run the tool again.

Permissions & Data Access

To work correctly, the tool needs permission to:

  • Read and edit the active Google Sheet, and

  • Access your basic Google account information (name and email address) provided by Google.

These permissions are used only to:

  • Detect duplicates in the sheet where you run the tool, and

  • Apply the necessary conditional formatting rules.

We do not store your sheet content on external servers or sell your data. For full details, see our Privacy Policy: https://www.logik.tv/privacy

Common Questions

Does this tool delete any rows or change my data?
No. Logik: Highlight Duplicates only adds or updates conditional formatting rules. Your underlying data (cells, text, and values) remains unchanged unless you manually edit or delete it.

Will the highlighting update when new data is added?
Yes. Because the tool uses conditional formatting, any new duplicates that appear in the formatted range will be highlighted automatically.

Can I remove the highlighting?
Yes. Use Format → Conditional formatting in Google Sheets™ and delete or modify the rule created by the tool.

Is this officially supported by Google?
No. Logik: Highlight Duplicates is built and maintained by Logik.tv and is not endorsed by or affiliated with Google LLC.

Getting Help

If you run into issues or have feature requests, we’d love to hear from you.

  • Find the form at the bottom of the page, fill it out, and we will get back to you as soon as possible!

When contacting support, please include:

  • A brief description of the problem,

  • Whether the issue happens in one sheet or all sheets, and

  • Any error message you see in Google Sheets™ or in the add-on sidebar/dialog.

Trademarks

Google, Google Sheets™, Google Workspace™, and Google Workspace Marketplace™ are trademarks of Google LLC. Logik: Highlight Duplicates is an independent tool and is not endorsed by or affiliated with Google LLC.

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