What can be cleaned automatically?

Whitespace trimming, empty-row removal, exact-duplicate removal, and header normalization to snake_case with unique names.

Does cleaning change the original file?

No. The original is only read in memory; the cleaned result is a separate export you choose to download.

How do I know what was removed?

Badges next to the Filters row show how many empty and duplicate rows were dropped.

Can I trust this with sensitive data?

Yes. Cleaning runs entirely in your browser, and you can verify it offline through the Verify Security panel.

Clean a messy CSV online, privately

Real CSV exports arrive with trailing spaces, blank lines, duplicate records, and headers like "Full Name (2024)". This page fixes all of that before you export, and it does the work in your browser rather than on a server.

Turn on Trim Whitespace, Remove Empty Rows, and Deduplicate, and each toggle updates the preview immediately with a badge count so you can see exactly what was removed.

Markdown / CSV Output

Drop a file to clean and export it

Processing stays in this browser. Guests can process up to 500 rows per file.

How to use this tool

1Drop the messy CSV file.
2Enable Trim Whitespace and Remove Empty Rows (both are on by default in the Tables workspace).
3Turn on Deduplicate and Normalize Headers as needed.
4Export the cleaned CSV or Markdown.

Frequently asked questions

What can be cleaned automatically?: Whitespace trimming, empty-row removal, exact-duplicate removal, and header normalization to snake_case with unique names.
Does cleaning change the original file?: No. The original is only read in memory; the cleaned result is a separate export you choose to download.
How do I know what was removed?: Badges next to the Filters row show how many empty and duplicate rows were dropped.
Can I trust this with sensitive data?: Yes. Cleaning runs entirely in your browser, and you can verify it offline through the Verify Security panel.

Private by design

This tool runs entirely in your browser. Files, tables, and results are never uploaded to a server — you can even disconnect your network and keep working. See the Privacy Policy.