Convert CSV to JSON

Reads input exactly as /api/csv/format does (same delimiter and header detection) and converts it to JSON. shape=objects gives one object per row, keyed by the header names (an empty name becomes column_N; a repeated name gets _2, _3, …). shape=arrays gives one array per row, the header row first. auto is objects when there is a header. Without types every value is a string, exactly as written. With types, a column whose values are all integers or numbers becomes JSON numbers (every digit kept, even beyond 2^53), a true/false column becomes booleans, and empty values become null; text, date and mixed columns stay strings. CSV with errors (see the format operation) is rejected rather than guessed at.

Browser version (runs locally): CSV Validate & Format.

Parameters

Also accepted on every endpoint: format (json | text). Parameters may come from the query string, a JSON object body, an urlencoded or multipart form, or (for input) a text/plain body.

Response 200 application/json

Text output (format=text, text/plain): The JSON text.

Errors

Errors are JSON: {"error": "<message>", "code": "<code>", "param": "<name>"?}.

Behaviour

• Idempotent: the same arguments always return the same result.
• Requires a client ID and secret (authentication). Each call is recorded as one metadata row against your client ID; inputs and outputs are never stored or logged. Responses carry cache-control: no-store.
• CORS: any origin may call this endpoint from a browser, using your credentials.

Examples

Responses below were produced by running each request through this code at build time. Long strings are shortened.

curl -X POST 'https://util.caruana.me/api/convert/csv-to-json' \
  -H 'content-type: application/json' \
  -d '{"input":"id,name,price,in_stock,added\n1,Widget,9.99,true,2024-03-01\n2,\"Gadget, mini\",12,false,\n3,Gizmo,,true,2024-04-15\n","types":true}'

{
  "json": "[\n  {\n    \"id\": 1,\n    \"name\": \"Widget\",\n    \"price\": 9.99,\n    \"in_stock\": true,\n    \"added\": \"2024-03-01\"\n  },\n  {\n   … (211 more characters)",
  "value": [
    {
      "id": 1,
      "name": "Widget",
      "price": 9.99,
      "in_stock": true,
      "added": "2024-03-01"
    },
    {
      "id": 2,
      "name": "Gadget, mini",
      "price": 12,
      "in_stock": false,
      "added": null
    },
    {
      "id": 3,
      "name": "Gizmo",
      "price": null,
      "in_stock": true,
      "added": "2024-04-15"
    }
  ],
  "shape": "objects",
  "header": [
    "id",
    "name",
    "price",
    "in_stock",
    "added"
  ],
  "rowCount": 3,
  "columns": [
    {
      "name": "id",
      "type": "integer",
      "empty": 0,
      "distinct": 3,
      "maxLength": 1
    },
    {
      "name": "name",
      "type": "text",
      "empty": 0,
      "distinct": 3,
      "maxLength": 12
    },
    {
      "name": "price",
      "type": "number",
      "empty": 1,
      "distinct": 2,
      "maxLength": 4
    },
    {
      "name": "in_stock",
      "type": "boolean",
      "empty": 0,
      "distinct": 2,
      "maxLength": 5
    },
    {
      "name": "added",
      "type": "date",
      "empty": 1,
      "distinct": 2,
      "maxLength": 10
    }
  ],
  "dialect": {
    "delimiter": ",",
    "delimiterDetected": true,
    "lineEnding": "lf",
    "hasHeader": true,
    "headerDetected": true,
    "bom": false
  }
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "csv_to_json",
    "arguments": {
      "input": "id,name,price,in_stock,added\n1,Widget,9.99,true,2024-03-01\n2,\"Gadget, mini\",12,false,\n3,Gizmo,,true,2024-04-15\n",
      "types": true
    }
  }
}

curl -X POST 'https://util.caruana.me/api/convert/csv-to-json' \
  -H 'content-type: application/json' \
  -d '{"input":"x\ty\n1\t2\n3\t4\n","shape":"arrays"}'

{
  "json": "[\n  [\"x\", \"y\"],\n  [\"1\", \"2\"],\n  [\"3\", \"4\"]\n]",
  "value": [
    [
      "x",
      "y"
    ],
    [
      "1",
      "2"
    ],
    [
      "3",
      "4"
    ]
  ],
  "shape": "arrays",
  "header": [
    "x",
    "y"
  ],
  "rowCount": 2,
  "columns": [
    {
      "name": "x",
      "type": "integer",
      "empty": 0,
      "distinct": 2,
      "maxLength": 1
    },
    {
      "name": "y",
      "type": "integer",
      "empty": 0,
      "distinct": 2,
      "maxLength": 1
    }
  ],
  "dialect": {
    "delimiter": "\t",
    "delimiterDetected": true,
    "lineEnding": "lf",
    "hasHeader": true,
    "headerDetected": true,
    "bom": false
  }
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "csv_to_json",
    "arguments": {
      "input": "x\ty\n1\t2\n3\t4\n",
      "shape": "arrays"
    }
  }
}