JSON to CSV Converter

When would you convert JSON to CSV?

JSON is great for APIs and JavaScript, but spreadsheet users and business analysts often need CSV. Converting a JSON export from a REST API into CSV lets you open it in Excel, Google Sheets, or any BI tool immediately, without writing a script.

What JSON shape is required?

The input must be a JSON array of objects, for example:

[
  {"name": "Alice", "age": 30},
  {"name": "Bob",   "age": 25}
]

Each object becomes one CSV row. The union of all keys across all objects forms the header row. Objects with missing keys produce empty cells.

Flattening nested objects

When Flatten nested objects is enabled, deeply nested JSON is collapsed into single-level columns using dot notation:

{"user": {"name": "Alice", "age": 30}}
-> columns: user.name, user.age

Arrays inside objects are kept as-is (not flattened), since there is no meaningful single-cell representation for a variable-length list.

Choosing the right delimiter

In many European countries, commas are used as decimal separators, so CSV files use semicolons as the field delimiter instead. Use the semicolon option when the file will be opened in a French, German, or other European locale spreadsheet application. Tab-delimited (TSV) files work well when field values may contain commas.

Excel compatibility

When opening a CSV file in Microsoft Excel, non-ASCII characters (accented letters, emoji, Chinese characters) may display incorrectly if the file is UTF-8 encoded without a byte order mark. Excel expects a UTF-8 BOM (\xEF\xBB\xBF) at the start of the file to correctly detect the encoding. Enable the "Include UTF-8 BOM" option to ensure correct display in Excel and other Windows applications.