JSON TO CSV, LOCALLY
Turn a JSON object array into CSV.
Convert an array of JSON objects to CSV with union columns, escaped commas, quotes and newlines, and clear handling for null and missing values.
Paste a JSON array of objects, then convert.
Conversion method and example
The top-level JSON value must be an array of objects. CSV columns are the union of keys in first-seen order. A missing key and a JSON null become empty cells; strings and scalar values become text. Nested arrays and objects become compact JSON text inside that cell. Cells containing commas, quotes, or line breaks are quoted, and embedded quotes are doubled, following RFC 4180 conventions.
For example, [{"name":"Ada","note":"hello, world"},{"name":"Grace","active":true}] produces columns name,note,active; the second row has an empty note cell, and the comma-containing first note is quoted. Inputs are limited to 100,000 characters and 10,000 rows. Conversion is local; no file or input is uploaded. CSV does not neutralize spreadsheet formulas, so treat untrusted cells carefully before opening the file in spreadsheet software. Page content updated November 3, 2026.
Good to know
Can I convert a single JSON object?
Use an array containing one or more objects. A top-level object, scalar, or array containing non-object values is rejected.
How are different object keys handled?
The CSV header contains each key once, ordered by the first time it appears. Rows without a key have an empty cell in that column.
How are nested values converted?
Nested arrays and objects are serialized as compact JSON text within one CSV cell. They are not expanded into additional rows or columns.
What happens to null?
A null value and a missing key both produce an empty cell. This means those two cases are not distinguishable in the resulting CSV.
Is my data uploaded?
No. Parsing and conversion run in this browser tab; the page does not upload or save the input.
Is it free?
Yes, during beta. Optional usage-credit plans are coming soon. Payments are not available and no credits are required.
Sources
CSV quoting and record conventions are based on RFC 4180. JSON values are parsed with the browser's native JSON parser. Sources checked November 3, 2026.
How it works
1. Paste a JSON array of objects. 2. Review the CSV using keys in first-seen order. 3. Copy or download the result; data stays in this browser tab.
Good to know
What JSON input is accepted?
The top-level value must be an array containing only objects. Nested objects and arrays are written as compact JSON text in their CSV cell.
How are columns chosen?
The converter collects the union of object keys in first-seen order. An object without a column gets an empty cell.
How are commas, quotes, and line breaks handled?
Cells containing a comma, double quote, carriage return, or line feed are quoted, and each embedded double quote is doubled, following RFC 4180 conventions.
What happens to null values?
A JSON null and a missing object key both become an empty CSV cell; other scalar values become text.
Is my JSON uploaded?
No. Parsing and conversion happen locally in this browser tab; the tool does not upload or save your JSON.
Is it free?
Yes, during beta. Optional usage-credit plans are coming soon. Payments are not available and no credits are required.