JSON to CSV Converter

This tool converts JSON data into CSV (Comma-Separated Values) format entirely in your browser. No data leaves your device. Transform JSON to CSV with support for nested objects, arrays, JSONLines, and multiple delimiters.

Supported input formats

• Array of objects — [{"a":1},{"a":2}] (most common)
• Single object — {"a":1,"b":2} becomes one row
• Object with array property — {"users":[...]} auto-detected
• JSONLines / NDJSON — one JSON object per line, no outer array
• File upload — .json or .txt files
• URL fetch — load JSON from a public URL (subject to CORS)

Output options

• Delimiters: comma, semicolon, tab, pipe, or a custom character
• Header row: include or exclude column names
• Force quotes: wrap every field value in double quotes
• Flatten nested: expand nested objects using dot notation (e.g. user.address.city), or keep them as JSON strings inside the cell

How nested JSON is handled

When Flatten nested is on (default), nested objects are expanded into separate columns using dot notation. For example:

• {"name":"Alice","address":{"city":"NYC","zip":"10001"}}
• Becomes columns: name, address.city, address.zip

When Flatten nested is off, nested objects and arrays are written into their cell as a JSON string. This preserves the original structure for a later pass.

Arrays inside values are kept as JSON text in both modes, since they cannot be represented as a single scalar cell value.

FAQ

Is this JSON to CSV converter free?

Yes, completely free. No login, no registration, no usage limits, no ads. The tool runs entirely in your browser.

Is my data safe?

Yes. All conversion happens locally in your browser using JavaScript. Your JSON data is never sent to any server, logged, or stored. You can disconnect from the internet after the page loads and the tool will still work.

What JSON structures does this converter support?

Arrays of objects, single objects, objects containing an array property (auto-detected), and JSONLines / NDJSON format (one JSON object per line). You can also convert JSON to CSV from a file or a URL.

How do I open the CSV in Excel or Google Sheets?

Click "Download .csv" and open the file in Excel, Google Sheets, or any spreadsheet application. If your locale uses semicolons as decimal separators (common in European regions), switch the delimiter to semicolon before downloading.

Can I convert CSV back to JSON?

This tool focuses on converting JSON to CSV. For the reverse direction, search for a "CSV to JSON" converter.

Is there a file size limit?

There is no imposed limit. Conversion happens in your browser's memory, so extremely large inputs (tens of MB) may be slow depending on your device. The tool works well for typical API responses and data exports.