Structured Data

CSV to JSON

Paste or upload CSV and get clean JSON instantly. Auto-detect the delimiter, choose whether the first row is a header, and let the tool infer numbers, booleans, and empty values. Your data never leaves the page.

Runs in your browser v1.0.0

Input & options

live

Delimiter

Value types

Output shape

Parsing

First row is a header Pretty-print

Upload CSV

Input CSV

source

Quoted fields, embedded commas, and line breaks inside quotes are handled.

JSON output

result

Read-only result. Copy or download it with the buttons above.

How it works

CSV is parsed locally with quote-aware parsing, so commas and line breaks inside quoted fields are preserved. The delimiter can be auto-detected or set manually. With a header row, each record becomes a JSON object keyed by the column names; duplicate or blank headers are given safe, unique names. In auto mode, numeric and boolean values are typed, empty cells become null, and strings with leading zeros (like ZIP codes) stay text so no data is corrupted. Nothing is sent to a server.

Practical uses

Convert CSV rows into JSON, with control over the delimiter, headers, output shape and value typing.

Common ways to use it

Turn a spreadsheet export into JSON for an API fixture or test data.
Convert a CSV log into an array of objects for quick analysis.
Produce a compact array of arrays when the header should not become JSON keys.

Headered CSV to typed objects

Input

id,name,active
1,Ada,true
2,Grace,false

Output

[
  {
    "id": 1,
    "name": "Ada",
    "active": true
  },
  {
    "id": 2,
    "name": "Grace",
    "active": false
  }
]

Verified with the tool's conversion function using the defaults: auto-detect delimiter, first row is a header, auto value typing, array of objects, pretty-printed. It detects the comma delimiter and reports 2 rows and 3 columns. In auto mode empty cells become null and values such as 05201 stay text to preserve leading zeros.

Options that matter

Delimiter — auto-detect or force comma, semicolon, tab, or pipe.
Value types — auto-detect numbers and booleans, or keep every value as text.
Output shape — array of objects keyed by the header, or array of arrays.
Parsing — treat the first row as a header; pretty-print the JSON or emit it minified.

Things to keep in mind

The output shape depends on the delimiter, header, typing, and shape settings, so check them for each file.
Blank and duplicate headers are given unique safe keys, for example column_2 and name_2.
An unterminated quoted field is reported as an error instead of emitting partial JSON.
Conversion runs in the browser; no data is sent to a server.