- How do I convert CSV to JSON?
- Paste your CSV into the editor, or open or drop a .csv, .tsv or .txt file (a file over 2 MB is converted in the background without filling the editor). The tool converts it as you type and shows a live preview table, with each column's type, and the generated JSON — click "Download" or "Copy JSON" when you're happy with the result.
- Does it use the first row as headers?
- Yes, by default. The first CSV row becomes the object keys for every row below it. Turn off "First row is headers" to treat every row as data — rows are then keyed column_1, column_2, and so on.
- What delimiters are supported?
- Comma, semicolon, tab, and pipe, plus an auto-detect option that picks the delimiter from the file — useful for exports from spreadsheet apps or locales that use something other than a comma. A file with one column (a list of emails, say) works too. Excel exports that aren't UTF-8 are read as Windows-1252, so accents survive.
- What are the output format and empty value options for?
- Output format switches between an array of objects (keyed by header), an array of arrays (with the header row kept as the first array, or not), an object keyed by a column of your choice, and JSON Lines (one object per line). Empty values controls what happens to blank cells — keep them as empty strings, convert them to null, or omit the field entirely. Values are typed per column: a column is numbers only if every value is a plain number (so 01234 and 19.90 are never mangled), true/false in any case becomes a boolean, and you can override any column's type, read decimal commas, or keep everything as text. Headers like address.city can be nested into objects.
- What happens if my CSV is malformed?
- A row with more or fewer fields than the header is converted anyway: short rows are padded with empty cells, extra fields get a column of their own, and each such row is listed by line number so you can click straight to it. Repeated or empty header names are renamed and the tool says so. Only an unclosed quote stops the conversion, and that error gives its line too.
- Is anything uploaded to a server?
- No. Your CSV, and the JSON generated from it, never leave your browser — nothing is uploaded or stored. It's free with no sign-up.