JSON to CSV Converter
Convert JSON to CSV and CSV back to JSON, with proper quoting and headers.
Runs entirely in your browser — your input never leaves your deviceAbout this tool
This converter turns a JSON array of objects into CSV, and turns CSV back into JSON — switch direction with one click. Going to CSV, it builds the header from the union of every object's keys and quotes any field that contains a comma, quote or line break. Going to JSON, it parses quoted fields and escaped quotes correctly (RFC 4180) and coerces numbers and booleans.
Good to know
- JSON input should be an array of flat objects; nested objects and arrays are stored as JSON strings in the cell.
- CSV input must have a header row — those names become the JSON keys.
- Switching direction feeds the current output back in, so you can round-trip in a click.
Everything runs in your browser, so even sensitive data never leaves your device.
Frequently asked questions
How do I convert JSON to CSV?
Paste a JSON array of objects in the JSON → CSV mode. The tool creates a header row from all the keys and a data row per object, quoting anything that needs it, ready to open in Excel or Sheets.
How do I convert CSV to JSON?
Switch to CSV → JSON and paste CSV with a header row. Each row becomes an object keyed by the header, and numbers and true/false are converted to real JSON types.
Does it handle commas and quotes inside fields?
Yes. The CSV parser follows RFC 4180, so fields wrapped in quotes can contain commas, line breaks and escaped double-quotes without breaking the columns.
What happens to nested objects?
When converting JSON to CSV, a nested object or array in a value is written as a compact JSON string in that cell, since CSV is a flat format.
Is my data uploaded?
No. Conversion runs entirely in your browser — nothing is sent to a server, which matters for private datasets.
Related developer tools
Explore more free tools
Every category runs free in your browser — nothing is uploaded.