CSV to JSON converter

Because “Convert numbers and booleans” turned 01234 into the number 1234. Codes, postcodes and phone numbers are text that happens to be made of digits, so untick that option and every value comes through as a string.

A nested object or array is written into the cell as JSON text, and the tool tells you how many values that affected. CSV is a flat format with no way to express nesting, so the alternative would be to lose the data.

Yes. Detection is automatic and usually right, and you can force comma, semicolon, tab or pipe if a file confuses it — which happens with European exports where the decimal separator is also a comma.

Both the input text and the parsed result sit in your browser’s memory at once, and a larger file will make the tab stall, especially on a phone. Above a megabyte a spreadsheet application or a command-line tool is the right instrument.