JSON/CSV変換

This converter turns a JSON array of objects into CSV and parses CSV back into JSON, in both directions. Pick the direction, paste your data, choose the delimiter, and copy the result.

It is handy for moving data between spreadsheets, APIs and config files, and the whole conversion is client-side, so your data stays private.

It expects JSON as an array of objects, like [{"name":"Mo","age":3}]. The CSV columns are the union of all the keys across the objects, a single object becomes one row, and any nested value is written as JSON text inside its cell.

It follows the standard CSV quoting rules, so a value that contains the delimiter, a quote or a line break is wrapped in quotes and escaped correctly, and the CSV parser reads those values back without losing data.

You can choose comma, semicolon or tab as the delimiter. Comma is the default and most common; semicolon suits regions where the comma is the decimal separator and spreadsheets expect it; tab produces TSV.

When reading CSV back into JSON, it infers types sensibly: plain numbers and true/false become real JSON values, while a value with a leading zero such as 007 stays as text so identifiers and codes are not mangled.