Remove Duplicates

Delete duplicate rows from a CSV or Excel file. Match on every column, or only on the ones that matter, like email address.

  • Pick the columns
  • Ignore case & spaces
  • See the duplicates
  • Nothing uploaded
No upload. No sign-up. No set size limit.
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Your files are processed on your own device. Nothing is uploaded, stored or seen by us.

How it works

How to remove duplicate rows

  1. Add your file

    Drop a CSV or Excel file. The first copy of each row is kept and later copies are removed.

  2. Choose what counts as a duplicate

    Tick columns such as Email to remove rows that share it, even if other columns differ.

  3. Download

    Save the cleaned file as CSV or Excel, or download just the duplicates to review them.

Why this converter

Deduplicate a list in seconds

Column-based matching

Find duplicates by email, ID or any mix of columns.

Forgiving comparison

[email protected] and "[email protected] " count as the same when you want them to.

Order kept

The first time a row appears is kept, in its original position.

Review what goes

Switch to "Only the duplicates" to check exactly what was removed.

Works on huge lists

Hundreds of thousands of rows take a second or two.

Private

Mailing lists and customer data stay on your computer.

More data tools: Compare two files · VLOOKUP / join · Large CSV viewer · CSV editor · CSV workflow · VCF to CSV · CSV to VCF · Split CSV · Merge CSV · Clean CSV · Transpose · Excel to JSON · Excel to SQL · CSV to Markdown · HTML table to CSV

Converters: JSON to CSV · CSV to JSON · JSON to Excel · TXT to CSV · XML to CSV · XLSX to CSV · CSV to Excel

FAQ

Questions

How do I remove duplicates from a CSV file?

Drop the file on the tool above. Duplicate rows are removed straight away; the count is shown above the preview, and you click Download CSV.

Can I remove duplicates based on one column?

Yes. Tick that column (for example Email) under "Compare these columns". Rows with the same value there are treated as duplicates, and the first one is kept.

How do I remove duplicates in Excel?

In Excel, select the data, go to Data › Remove Duplicates, tick the columns to compare and click OK. That works for one sheet; this tool also ignores case and spaces and lets you see what was removed.

Which copy is kept?

The first one, the row nearest the top. All later copies are removed.

Does it change the order of my rows?

No. The remaining rows stay in their original order.

Are my files uploaded?

No. Everything runs in your browser, so your data never leaves your computer. It works offline once the page has loaded.