Developer Tools
JSON to CSV
Convert a JSON array of objects into CSV with a header row. Keys are auto-detected from the union of every object — missing fields become empty cells. Nested objects and arrays are JSON-stringified so nothing is lost.
Your input is processed locally in your browser. It is not uploaded to Dueneo.
Loading JSON to CSV…
How to use
- 1
Paste a JSON array
The top-level value must be an array of objects. Each object becomes one CSV row.
- 2
Pick a delimiter
Comma is the default; choose semicolon for European locales, tab for TSV exports, or pipe for legacy systems.
- 3
Convert to CSV
Keys are collected from every object in first-seen order. The first row of the output is the header.
- 4
Copy or save
Use Copy for the clipboard or Save to download data.csv. Fields with commas or newlines are automatically quoted.
Common use cases
- Export API results for a spreadsheet user.
- Generate a CSV download from a JSON-backed admin panel.
- Snapshot a NoSQL collection into a single CSV for inspection.
- Convert a JSON fixture into CSV for a legacy importer.
Limitations
- The input must be a JSON array of objects — single objects or nested arrays are not supported.
- Nested objects and arrays are JSON-stringified into a single cell rather than flattened.
- Inputs larger than 1 MB are rejected to keep the tab responsive.