What this tool checks
A CSV file is valid when records split on a delimiter, quoted fields may contain that delimiter or line breaks, and quotes inside fields are doubled. Spreadsheet exports often violate that contract: a missing closing quote, a stray comma in an address, or a mix of LF and CRLF.
This validator parses the file locally, reports those issues with row numbers, and offers a repaired copy that uses consistent column counts and RFC 4180 quoting. The original file is not overwritten.
What usually causes a \u201cbroken\u201d CSV
- Concatenating exports without normalizing quotes
- Copy-paste from Excel that injects unquoted commas
- Editors that convert line endings on some rows only
- A UTF-8 BOM that some importers treat as part of the first header
Example
Input with a short row:
id,name,qty 1,Nails,10 2,Hammer
Repaired output pads the missing field:
id,name,qty 1,Nails,10 2,Hammer,
Limitations
Repair cannot know whether a jagged row should have been quoted or split. If a comment field contained an unquoted comma, padding is the safe mechanical fix; you may still need to edit that row. Encoding problems belong in the encoding fixer.