A CSV can look ordinary until an import drops a leading zero, shifts a field into the wrong column, or overwrites a duplicate header. I built IndieCSV to make those problems visible before the import.
Open one file or paste its text. The table shows what the parser sees, and the issue list points to records that deserve a closer look. Everything runs locally in your browser. Your CSV does not go to a server, into a URL, or into analytics.
Inspect first, repair deliberately
Papa Parse reads the CSV. IndieCSV keeps its cells as strings and its records as arrays, then checks field counts and repeated headers. A delimiter guess is shown as a guess. You can choose comma, semicolon, tab, or pipe yourself.
You can add missing empty fields, remove empty records, trim whitespace, or prefix formula-like text with an apostrophe. Each option describes a change to your data. The preview lists the changed values before a download becomes available. Nothing is repaired merely because you opened a file.
Broken quoted fields need your judgment. They block export until you edit the original text and inspect it again. The tool cannot know where a missing quote was meant to go.
Keep the values you brought
CSV export quotes the fields, doubles internal quotes, and writes CRLF record separators, following the common format described in RFC 4180. This changes the serialization, but unselected cell values stay the same. JSON export is an array of row arrays, including the first record. Two columns with the same heading remain two columns.
A spreadsheet may still interpret a numeric-looking cell or run formula-like text when it opens a CSV. Import columns as text when identifiers matter. IndieCSV flags formula-like cells and offers an explicit apostrophe-prefix option based on OWASP’s guidance. That reduces risk; it does not promise safety across every spreadsheet and later edit. No formula is evaluated here.
One small workspace
The first release accepts UTF-8 text up to 2 MiB, with limits of 20,000 records, 250 columns, and 200,000 cells. The table is paginated. Larger files need splitting locally before inspection.
IndieCSV is not a spreadsheet, a cloud table, or a database connection. It keeps no automatic history. The core is free, with no account, card, premium plan, or hidden paywall. Cookieless DataFast measures page traffic and recognized AI crawler requests. Neither receives your file or pasted text.