CSV ⇄ JSON Converter

Convert CSV to JSON or JSON arrays to CSV instantly, with support for nested fields and custom delimiters — entirely in your browser.

Direction
Options
source.csv
output.json

Your Data Never Leaves Your Device

Every tool runs entirely in your browser. Nothing you type is uploaded, stored, or logged on our servers.

100% Client-Side

The CSV ⇄ JSON Converter handles both directions: paste a CSV export and get back a clean JSON array — with dotted column headers like address.city automatically expanded into nested objects — or paste a JSON array and get a properly quoted CSV file back, with nested objects flattened into dotted column names.

Quoted fields, embedded commas, and custom delimiters (comma, semicolon, tab, or pipe) are all handled correctly. Everything runs locally in your browser — nothing you paste is uploaded anywhere.

FAQ

Yes. The parser follows the standard CSV quoting rules — fields wrapped in double quotes can contain commas, line breaks, and escaped ("") quotes, and are parsed correctly rather than split on every comma.

Column headers containing a dot, like address.city, are expanded into nested objects — {"address": {"city": "..."}} — instead of a flat key literally named "address.city". Turn it off to keep headers as flat keys.

Yes — pick comma, semicolon, tab, or pipe from the delimiter dropdown. It applies to both parsing CSV input and writing CSV output.

With "Flatten nested objects" on, a nested value like {"address": {"city": "London"}} becomes a column named address.city. Arrays are kept as their JSON string representation inside a single cell, since CSV has no native way to represent a list in one field.

No. Both directions of the conversion run locally in your browser — nothing you paste is sent to a server.