This tool converts a JSON array of objects to RFC 4180 CSV format. Column headers are automatically derived from all unique keys across the objects. Fields containing commas, quotes, or newlines are properly quoted. Supports nested values as stringified JSON. Runs entirely in your browser.
JSON arrays of objects map cleanly to CSV: each object is a row, each unique key is a column. The tricky parts are deciding the header order when objects have different keys, and quoting fields that contain commas, double-quotes or newlines without breaking downstream parsers. This converter takes the union of keys in first-seen order and applies RFC 4180 quoting (a field with any of , " \n is wrapped in quotes; internal " becomes "").
Nested objects and arrays are JSON-stringified into a single cell, because CSV itself is intentionally flat — there is no spec for nested data. That output is round-trippable: you can JSON.parse the cell later if you need the structure back. Conversion happens entirely in the browser, with row and column counts shown alongside the output so you can sanity-check shape before importing into a spreadsheet.
The header row is the union of every key seen across the array, so missing fields just become empty cells. The order of the headers follows first-appearance order, which is usually what you want for diffs.
Per RFC 4180: any field containing a comma, double-quote or newline is wrapped in double-quotes, and any internal double-quote is escaped by doubling it (" becomes ""). That is the form Excel, Google Sheets and Postgres COPY all expect.
They are JSON-stringified into a single cell. CSV is intentionally flat, so nested structure is preserved as text — you can re-parse it later with JSON.parse if needed.
Yes. A single object is treated as a one-row array. If you have objects keyed by id, you may want to map them to an array first ([…Object.values(map)]) so the keys become a column.
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