CSV to JSON converter
Convert CSV to JSON: an array of objects, one per row. Quoted fields, embedded commas and line breaks are handled correctly, and the delimiter is detected for you.
What you get
- Convert CSV to JSON online: a CSV to JSON array of objects, one per row, with the delimiter (comma, semicolon, tab, pipe) detected for you.
- Quoted fields, commas inside values and line breaks inside cells are read correctly; broken quotes are reported with their line.
- Numbers and booleans detected only when the text stays identical, so 007, 1.50 and long IDs are never altered.
- Checked cell by cell against your original CSV.
- Excel to JSON: save the sheet as CSV, then open that CSV file to JSON here, one object per row.
- Private and free: everything runs in your browser, nothing is uploaded, and there is no sign-up.
How each result is checked
- The CSV is parsed with a strict parser that reports broken quotes.
- Every cell in the JSON is compared with the original cell text; nothing may change.
What can't convert exactly
- Number detection only converts values whose text stays identical, so 007, 1.50 and very long IDs stay text.
- Duplicate or empty header names are renamed, with a warning.
Questions
Why is 1.50 a string?
Because the number 1.5 would lose the trailing zero. Only values that convert without any change become numbers.
My file has no header row
Turn off "First row is header" to get an array of arrays.
How do I convert an Excel sheet to JSON?
In Excel, save the sheet as CSV (File > Save As > CSV UTF-8), then open that file here. Each row becomes a JSON object, an array of objects keyed by the header row.
How big a CSV file can I convert?
Files of several megabytes work; the limit is your browser’s memory, since nothing is uploaded.
How do I convert CSV to JSON online?
Paste your CSV or open a file on the left (or click Example). The JSON appears on the right as you type, already checked. Copy it, or download it as a file. Nothing is uploaded.
Can the JSON output be wrong?
Every result is checked before it is shown (the checks are listed on this page). If a check fails, the page says "Review needed" and why, instead of presenting the output as correct, and anything that cannot convert exactly is named in the notes.