JSON to CSV Converter
Turn an array of objects (or an array of arrays) into CSV. Objects with different keys are merged into a single column set so nothing is lost, and you can pick the delimiter and line ending.
How columns are chosen
For input like [{"id":1,"name":"a"}, {"id":2,"tag":"x"}] the columns become id, name, tag in order of first appearance, with missing values left empty. API responses can be pasted in as-is.
Escaping rules
Values containing the delimiter, a double quote, a line break or leading/trailing whitespace are wrapped in double quotes, with inner quotes doubled per RFC 4180. Nested objects and arrays are serialised as JSON strings.
Opening the result in Excel
Choose "UTF-8 with BOM" when downloading if the file will be double-clicked in Excel, and CRLF line endings for the smoothest experience.
Frequently asked questions
Does it flatten nested JSON?
Top-level keys become columns; nested objects and arrays are written as JSON strings rather than expanded into extra columns.
Can I omit the header row?
Yes, there is a checkbox — useful when appending to an existing file.
Can I convert a single object?
Yes, a lone object is treated as a one-row CSV.
What happens with invalid JSON?
The parse error is shown in the output area. Trailing commas and unclosed quotes are the usual culprits.