Turn arrays of objects into CSV rows and back again. Nothing is uploaded.
The JSON ↔ CSV Converter follows RFC 4180 quoting and auto-detects comma, semicolon and tab delimiters; on 7 tabular sample documents, pretty-printed JSON weighed 2.9× the CSV bytes.
This converter turns a JSON array of objects into CSV rows you can open in Excel or Google Sheets, and turns CSV back into JSON for APIs and scripts. The header row becomes the object keys, and each following row becomes one object.
JSON → CSV collects the keys of every object as columns, quotes fields that contain the delimiter, quotes or line breaks, and joins rows with the delimiter you pick. CSV → JSON auto-detects comma, semicolon or tab, honors quoted fields per RFC 4180, and can detect numbers, booleans and null. Everything runs in this tab.
No. This page never sends your input to a server — formatting, decoding and hashing all run in this tab, on this device.How that works.
An array of objects, where each object is one row. A single object becomes a one-row CSV. Nested objects or arrays inside a cell are stored as a JSON string in that cell.
Yes. When reading CSV the delimiter is detected from the header row, so semicolon-separated files from Dutch or German Excel installs convert without changes. For JSON → CSV you pick the delimiter yourself.
With it on, cells that look like numbers, true, false or null become those JSON types. With it off, every cell stays a string — safer for postal codes, phone numbers and IDs with leading zeros.
Per RFC 4180: the field is wrapped in double quotes and any quote inside it is doubled. Reading does the reverse, so values round-trip unchanged.
Browse alljson toolsor thefull tool directory.