How are nested objects flattened?

Nested objects become dot-path columns (address.city). Lists of plain values are joined with '; ' in one cell; lists containing objects stay as compact JSON text in one cell so one record stays one row. The rule is printed on the page.

Why does Safe export add an apostrophe?

A cell beginning with =, +, - or @ can be treated as a formula by Excel or Google Sheets. Safe export prefixes such fields with an apostrophe so they open as plain text instead of running as formulas.

Is anything uploaded?

No. JSON is parsed and converted in your browser tab. Nothing is uploaded, stored or shared.

JSON to CSV Converter — Flatten Nested JSON, Safe Export, Free

Free JSON to CSV converter. Paste or upload JSON, flatten nested objects into dot-path columns with the rule shown, preview the table, choose comma, semicolon or tab, and download a spreadsheet-safe CSV. Formula-injection warning included. Fully local — nothing uploaded.