Try Papa Parse

String
Local file(s)
Remote file
JSON to CSV

Choose one or more delimited text files for Papa to parse.



Or use one of these:
Normal file
Large file
Malformed file

Type the URL of the file to be downloaded and parsed.
(cross-origin requests must receive Access-Control-Allow-Origin header)



Or use one of these:
Normal file
Large file
Malformed file

Paste a valid JSON string to convert to CSV.

Results will show up in the console of your browser's inspector tools.
The file is loaded in chunks and results are delivered row-by-row during parsing. Saves memory and prevents crashes. Runs the parser in a separate thread so the web page doesn't lock up. Keys data by field name rather than an ordered array. Turns numeric data into numbers and true/false into booleans. The delimiting character. Usually comma or tab. Default is comma. If > 0, stops parsing after this many rows. Only applies when reading local files. Default is specified by the browser (usually UTF-8). If specified, skips lines starting with this character.