FREE CSV & TSV CLEANERLOCAL BY DESIGN

Messy spreadsheet?Clean it with confidence.

Remove duplicates, normalize text and review every change before exporting. Your file is processed only in this browser.

Clean a file for free

Your data never leaves your device

Duplicate removal
Whitespace cleanup
Email normalization
Excel-friendly CSV

PRIVATE WORKSPACE / 01

Clean your data

Start with the example, paste data or choose a local file.

Runs locally in your browser

Import data

Drop your CSV or TSV here or browse your files CSV, TSV or TXT · up to 8 MB · stays on your device

OR PASTE DATA

Input settings

Delimiter

File encoding

If accents or columns look wrong, change these settings.

Choose cleanup steps

Trim outer spacesRemove spaces at the beginning and end Fix repeated spacesTurn repeated spaces and tabs into one space Remove empty rowsDelete rows with no information Remove exact duplicatesKeep the first matching row

Compare duplicates by

Ignore uppercase / lowercase Lowercase email addressesOnly valid addresses in recognized email columns

Review and export

Sample loaded

ORIGINAL ROWS—

CLEAN ROWS—

ROWS REMOVED—

Cleaned preview

Showing up to 12 rows

The preview shows at most 12 rows and 25 columns; export includes the full table.

Adjust the options to preview changes instantly. Not uploaded

Protect formula-like valuesAdds an apostrophe before cells beginning with =, +, @ or a non-numeric −. This is safer for untrusted files but changes those exported cells.

Ready when you are.Your original file remains unchanged.

WHY CSV CLEANUP LAB

A small tool with clear boundaries.

Designed for common CSV cleanup without accounts, trackers or hidden automation.

Local processing

Reading, cleaning and file generation happen in your browser. CSV Cleanup Lab has no backend.

Visible changes

See row counts, cleanup details and a data preview before saving anything.

Practical export

Download UTF-8 CSV with Excel compatibility or copy a tab-separated table to your clipboard.

QUICK GUIDE

From spreadsheet to clean CSV in three steps.

Export a copy from Excel, Google Sheets or LibreOffice as CSV UTF-8, clean it here, then reopen the downloaded file to verify the result.

Direct XLSX import is not available in this version. Exporting to CSV first keeps the tool small, transparent and dependency-free.

1
Choose a copy
Keep the original spreadsheet and import a CSV, TSV or TXT copy.
2
Review the cleanup
Select only the rules you want and check the preview and counts.
3
Export safely
Leave formula protection on for untrusted data, then download or copy the result.

QUESTIONS

Good to know

Is CSV Cleanup Lab really free?

Yes. This validation-stage prototype is free and requires no account or credit card.

Is my spreadsheet uploaded?

No. The current app has no server or analytics. File contents stay in this browser tab.

Can I use it with Excel or Google Sheets?

Yes. Export your sheet as CSV UTF-8, clean it here, and open the downloaded CSV. Direct XLSX editing is not included.

Does it remove similar but non-identical entries?

No. Duplicate detection uses exact values after the selected normalization rules. It does not guess whether two people or records are the same.