How do I remove duplicate rows from a CSV file online for free?

Upload your CSV file above. The tool compares every row using an exact-match algorithm: rows are serialised as JSON strings and checked against a Set, so only the first occurrence of each unique row is kept. The deduplicated file downloads instantly.

How does duplicate detection work — is it an exact match or partial match?

The tool performs exact row-level matching: a row is considered a duplicate only if every cell in that row is identical to a previously seen row. Partial matches or fuzzy deduplication (e.g. similar but not identical values) are not applied — just true duplicates are removed.

Will removing duplicates change the order of remaining rows?

No. The original row order is preserved. The tool keeps the first occurrence of each duplicate group and removes all subsequent occurrences, so your data stays in the same sequence as the input file.

What if my CSV has no duplicate rows?

If no duplicate rows are found, the tool displays an informative message and does not produce a download file. This prevents accidentally downloading an identical copy of your original data under a different filename.

Is it safe to process a CSV with personal or confidential data?

Yes. The entire deduplication process runs inside your browser using the Papa Parse library — your file is never sent to any server. You can safely clean CSVs containing customer records, email lists, or any sensitive dataset.

CSV dedup

Remove Duplicate Rows

Clean your CSV by removing all duplicate rows instantly. Free, no upload required.

Your files are processed locally and never uploaded to our servers.

Drop a CSV here

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How it works

1
Upload your file
Drop your file or click to browse. No size limit.
2
Convert instantly
Processed in your browser — nothing is uploaded to any server.
3
Download the result
Your converted file is ready in seconds.

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