Convert JSON to CSV and CSV back to JSON, in your browser.
Converted locally — your data is never uploaded.
How do you convert JSON to CSV?
JSON → CSV uses the union of object keys as the header row and quotes any value containing a comma, quote or newline. CSV → JSON uses the first row as keys and auto-detects numbers and true/false. For example, a JSON array of two people becomes a CSV with a name,age header and one row each. It runs in your browser.
Understanding your result
CSV is ideal for spreadsheets; JSON is ideal for APIs. This converts losslessly for flat data; nested values are stored as JSON text inside a cell.
Formula and method
JSON → CSV uses the union of object keys as the header row and quotes any value containing a comma, quote or newline. CSV → JSON uses the first row as keys and auto-detects numbers and true/false.
Assumptions and limitations
Conversion is lossless for flat arrays of objects; nested objects and arrays are stored as JSON text inside a cell rather than expanded into columns. CSV to JSON auto-detects numbers and booleans, so identifier-like values may change type, and it expects a header row with comma delimiters and standard quoting.
Worked example
A JSON array of two people becomes a CSV with a name,age header and one row each.
How to use this tool
- Choose the direction (JSON → CSV or CSV → JSON).
- Paste your data.
- Copy or download the converted output.
Common mistakes to avoid
- Passing a single JSON object is fine, but JSON → CSV expects an array of objects for multiple rows.
- CSV without a header row — the first row is treated as the keys.
About the JSON to CSV Converter
Convert a JSON array of objects into CSV, or turn CSV with a header row back into JSON. Everything runs in your browser.
Who should use this tool
Developers and analysts moving data between APIs, spreadsheets and databases.
Benefits
- Convert both directions without installing any software
- Handle commas, quotes and newlines inside values safely
- Move API data into spreadsheets and back again
- Process everything in your browser with nothing uploaded
Practical use cases
- Turn an API's JSON response into a spreadsheet
- Import CSV exports back into JSON for a script
- Share flat data with non-technical colleagues as CSV
- Clean up and reshape tabular data quickly
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Frequently asked questions
Are commas inside values handled?
Yes. Values with commas, quotes or line breaks are quoted and escaped per the CSV standard.
Is my data uploaded?
No. Conversion happens entirely in your browser.
What happens to nested objects when I convert to CSV?
CSV is a flat format with no concept of nesting, so any nested object or array is kept as JSON text inside a single cell rather than spread across columns. The data is preserved and converts back cleanly, but if you need nested fields as separate columns, flatten the JSON before converting.