Toolivaro

Free JSON to CSV Converter

Convert a JSON array of objects into RFC 4180 CSV with correct quoting, column union, and copy or download.

Processed locally in your browser

Processed locally in your browser — data is never uploaded, logged, or stored.

How is the result calculated?

Exporting an API response to a spreadsheet

An API returns users with different fields — one has a city, another does not. The converter builds the column set from all keys (name, age, city), emits an empty cell where city is missing, and quotes the cell containing a comma. The result opens directly in spreadsheet software.

Input Value
json [{"name":"Alice","age":"30","city":"Paris"},{"name":"Bob","age":"25"}]
Result name,age,city Alice,30,Paris Bob,25,

What is the formula and its assumptions?

Column set

columns = union of all object keys, first-seen order

Symbol Meaning
union every key that appears in any object

Objects missing a key produce an empty cell in that column — the column order is stable across the file.

Cell quoting (RFC 4180)

quoted ⇔ cell contains comma, quote, or line break

Symbol Meaning
quote a double-quote inside a quoted cell is doubled ("")
line break CRLF is used between rows

What are the most common mistakes?

  • Converting a single object instead of an array — the converter requires a non-empty array of objects and explains why.
  • Expecting nested objects to be flattened — they are serialized as JSON strings, which is the only lossless flat representation.
  • Using an online converter that uploads the JSON — this tool keeps everything on your device.

What are the assumptions and limitations?

  • Input must be a non-empty array of objects; a bare object or array of primitives is rejected with a clear message.
  • Nested values remain JSON strings — true flattening of deep structures is outside the converter’s scope.
  • Very large arrays are processed in memory; the tool is designed for typical payloads, not database dumps.

Where do the numbers come from?

Last reviewed August 4, 2026 · Version 1.0.0 · Toolivaro does not guarantee external content.

Developer CSV to JSON Converter Convert CSV files and pasted tables into JSON objects with automatic delimiter detection and header mapping. Developer JSON Formatter & Validator Format and validate JSON with readable indentation, precise error messages, and byte-size stats — fully local. Developer JSON Minifier Compress JSON to its smallest valid form — strip all whitespace, count the bytes saved, and copy or download. Developer Base64 Encoder & Decoder Encode text or files to Base64 and decode back, with UTF-8 handling, validation, and size stats — fully local.

Frequently asked questions

How are nested objects converted?

Nested values are serialized as JSON strings inside the cell — for example {"x":1} becomes the text {"x":1}. CSV is a flat format, so deeper structures need flattening or a separate export.

What is the column order?

Columns follow first-seen order across the array: the first object contributes its keys in order, then new keys from later objects are appended. Every row lines up with the header regardless of which object has which keys.

Why does my file end with CRLF?

CRLF is the line ending of RFC 4180 and the convention spreadsheet applications expect. The converter emits it by default so files open correctly everywhere.

Found a mistake or have a correction? Report it — we review every correction.