Last reviewed August 23, 2026

How to Convert JSON to CSV Predictably

Convert arrays of flat objects or arrays into quoted CSV with deterministic columns and an explicit nested-data policy.

Use a deliberately tabular JSON shape

OpenFileTools accepts an array of flat objects or an array of arrays. It rejects mixed shapes because inventing a table from arbitrary nested JSON would create unclear or lossy spreadsheet semantics.

Deterministic object columns

For object arrays, columns follow first-seen key order across records. The union includes keys introduced later, and missing values become empty cells without changing other records.

CSV quoting protects structure

Fields containing the chosen delimiter, a quote, carriage return, or line feed are enclosed in quotes, and quotes are doubled. This preserves the cell boundary when the CSV is parsed again.

Nested values require an explicit decision

Nested arrays and objects are rejected by default instead of becoming [object Object]. If you explicitly choose JSON stringification, the nested JSON text is stored inside one correctly quoted CSV cell.

Convert, preview, and download

Paste or load JSON, select comma, semicolon, tab, or pipe, choose the nested-value policy, and convert. Inspect the bounded table preview before downloading the CSV.

  • CSV does not preserve JSON types reliably.
  • Keep the JSON source as the authoritative structured copy.
  • Open the result in the intended destination before deleting source data.
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Open JSON to CSV