How are empty cells handled?

Empty cells become empty strings by default. Enable type inference if you would rather get null for blanks.

Can I convert a large spreadsheet export?

Yes — paste the file contents and the converter processes every row locally.

Convert CSV to JSON with automatic header detection, delimiter detection and RFC 4180 quote handling — processed entirely in your browser.

Convert spreadsheet data into clean, typed JSON.

Quoted fields are parsed with RFC 4180 rules, so delimiters and line breaks inside quotes survive the round trip.

Your CSV0 lines

Delimiter

First row is a headerInfer numbers and booleansBlank cells become null

The whole flow runs in your browser — nothing is uploaded.

Paste your CSVInclude the header row if your file has one.
Check the optionsDelimiter and header row are detected automatically and can be changed.
ConvertPress Convert to JSON and review the output.
ExportCopy the JSON or download it as a .json file.
Every step runs locally in your browser.

Turn CSV rows into clean JSON with header detection. Everything runs client-side on your own device.

RFC 4180 parsingQuoted fields, embedded commas, escaped quotes and multi-line values are handled.
Header detectionKeys come from the first row — or generated keys if your file has no header.
Type inferenceOptionally convert numeric and boolean-looking cells to real JSON values.
Private conversionYour data stays in your browser.

Comma, semicolon, tab and pipe. Detection picks the character that splits the first rows most consistently, and you can override it.