CSV ↔ JSON Converter: Moving Data Between Spreadsheets and Code
CSV is what spreadsheets love; JSON is what APIs and code love. Converting between the two is a common preparatory step — exporting Excel data for an API, or importing JSON returns into a sheet.
CSV is flat — rows and columns, with the first row usually as headers. JSON is hierarchical — objects can contain arrays containing more objects. CSV → JSON is straightforward: each row becomes an object keyed by the headers. JSON → CSV requires flattening any nested data, which can get messy if the JSON is deeply nested.
Conversion gotchas
- •Commas inside CSV values must be quoted, or they'll be misinterpreted as column separators
- •Newlines inside CSV cells need quoted/escaped values
- •JSON null values become empty strings in CSV
- •Nested JSON arrays/objects don't map naturally to CSV — need flattening or stringification
- •Dates: JSON has no date type, so they're strings; CSV interpretation depends on the spreadsheet locale
Extended FAQ
Why do my Korean characters look broken in CSV?
CSV file encoding. Excel often defaults to a non-UTF-8 encoding for legacy reasons. Save as 'CSV UTF-8' (or include a BOM) for Korean text to display correctly.
Are my files uploaded?
No — runs entirely in your browser.