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CSV Data Cleaner

Clean messy CSVs — trim whitespace, fix encodings, deduplicate rows, standardize blanks. Make client exports analysis-ready — local processing, free, no signup.

100% Local Browser Native

How to Use the CSV Data Cleaner

1. Paste messy CSV

Client exports with whitespace and encoding issues.

2. Run cleaning passes

Trim, dedupe, and standardize in order.

3. Copy clean CSV

Verify row counts before analysis.

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Frequently Asked Questions

What gets cleaned?

Leading/trailing whitespace, BOM markers, inconsistent line endings, blank rows, and exact duplicates. A typical client export needs all five.

Encoding issues?

Latin-1 vs UTF-8 mojibake (é for é) detects and converts. Confirm the source encoding first — wrong guesses double-corrupt.

Blank vs null?

Standardize empties to one representation (empty or NULL) per downstream need. Mixed blanks break GROUP BY counts silently.

Does cleaning upload my CSV?

No — cleaning runs locally in your browser. Data never leaves your device.

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Last updated October 2026