NextTool

Remove Duplicate Rows

How to use

Scans CSV data for exact-match duplicate rows and removes them, telling you how many were found and removed. Paste or upload your CSV and download the de-duplicated version.

Excel & CSVLocal only

Step 1 of 3: Upload

  1. 1
  2. 2
  3. 3

Step 1 of 3 · Upload

CSV / TSV input

Delimiter
When to use this
  • Cleaning up a contact list that accidentally has repeated entries from multiple imports
  • Removing duplicate rows after merging several data exports together
  • Verifying a dataset is unique before loading it into a database with a uniqueness constraint
  • Tidying up a spreadsheet before sending it to a client or teammate

Free and private. Everything runs on your own device, with no account and no uploads.

This tool scans a CSV or TSV file and removes any rows that are exact duplicates of an earlier row, keeping the first occurrence and reporting how many duplicates were removed. It is a quick way to clean up a data export that has accidental repeats before importing it elsewhere. The deduplication logic runs entirely in your browser using row-by-row comparison, not a spreadsheet engine.

This tool is built for delimited text data such as CSV and TSV; it does not parse binary Excel workbooks directly.

It compares the full contents of each row (excluding the header) against previously seen rows and flags an exact match as a duplicate.

The first occurrence of each unique row is kept, and later exact repeats are removed.

No, it only removes exact row matches; rows that differ by even a single character or extra space are treated as distinct.

How it works
  1. 1

    Upload or paste your data

    Load the CSV or TSV file you want to deduplicate.

  2. 2

    Set the correct delimiter

    Confirm the delimiter matches your data format.

  3. 3

    Review the deduplicated table

    Check the count of duplicate rows that were removed.

  4. 4

    Download the cleaned file

    Save the deduplicated CSV to your device.

More in Excel & CSV
CSV Viewer
View and browse CSV files in a clean table layout in browser
CSV Editor
Edit CSV data in an interactive spreadsheet-style table editor
CSV Cleaner
Remove extra spaces, fix encodings, and sanitize CSV data automatically
CSV to JSON
Convert CSV files to JSON arrays with configurable key mapping
Read about this
Merging CSV files whose columns do not line up3 minCleaning messy spreadsheet data: a repeatable order of operations3 minCSV or Excel? Choosing the right format for the job3 min
Pro tips
  • ·Run the CSV Cleaner first to trim whitespace, since a trailing space can make otherwise-identical rows count as unique.
  • ·This checks the whole row, not a single key column, if you need dedup by one field only, sort or filter manually afterward.
  • ·Keep a copy of the original file until you've confirmed the removed count and result look correct.