Several issue types occur together.
Use CSV Cleaner.
SPARKPOND / CATEGORY
Free Online Data Cleaning Tools
Cleaning is safer when each assumption is visible. These tools preview exact changes and keep the original file untouched.
Problems covered
What you can solve
- ✓ Repeated records.
- ✓ Mixed null markers.
- ✓ Ambiguous dates.
- ✓ Garbled characters or wrong delimiters.
9 tools
Tools in this category
Free Online CSV Cleaner
Clean CSV or TSV files locally, preview ordered repairs and download a checked CSV without an account. Duplicates, blanks, headers and dates stay under your control.
Open →Remove Duplicate Rows from a CSV
Remove exact or key-based duplicates from CSV or TSV locally. Preview the row-count impact, keep the first, last or most complete row, and download without an account.
Open →Find and Fix Missing Values in a CSV
Find blank, null, N/A, NA and dash markers in CSV or TSV locally. Keep, fill, remove or quarantine affected rows and download checked outputs without an account.
Open →Normalize CSV Dates to ISO 8601
Normalize CSV or TSV dates to ISO 8601 locally after explicitly confirming a day-first or month-first convention. Preview changed cells without an account.
Open →Fix Garbled CSV Characters and Encoding
Fix UTF-8, BOM, Windows-1252 or Latin-1 CSV text locally. Compare decoding previews for é, ’ and Â, then export UTF-8 without an account.
Open →Change a CSV Delimiter Online
Change a CSV or TSV delimiter locally between comma, semicolon, tab and pipe. Preserve quoted separators, preview columns and download without an account.
Open →Clean and Rename CSV Column Headers
Clean empty, duplicate or padded CSV headers locally. Preview unique old-to-new column names and download a checked CSV without an account.
Open →Remove Spaces from CSV Cells
Trim leading, trailing and non-breaking whitespace from selected CSV or TSV columns locally. Highlight changed cells and export without an account.
Open →Remove Empty Rows from a CSV
Remove fully blank or whitespace-only CSV rows locally after reviewing the count. Configure null markers and download a checked CSV without an account.
Open →Choose well
Which tool should you use?
The text looks like é or ’.
Use Fix CSV Encoding.
Rows repeat by email or ID.
Use Remove Duplicates.
Guides
Understand these problems
How to Fix UTF-8 and Windows-1252 CSV Encoding
Garbled text appears when bytes are decoded with a different character encoding from the one used to create the file.
Read →How to Remove Duplicate Rows from a CSV
Duplicates must be defined by all columns or by stable business keys before rows are removed.
Read →CSV Comma vs Semicolon: Which Delimiter Should You Use?
Both formats are valid delimited text; compatibility with the destination matters more than the extension.
Read →FAQ
Category questions
Will cleanup change the original file?
No. Operations apply to a working copy and export a new file.
Are ambiguous repairs automatic?
No. Dates, encodings and destructive choices require confirmation.
Can I combine cleaning steps?
Yes. CSV Cleaner provides an ordered, reversible pipeline.