CSV to JSON Converter

Convert CSV files into structured JSON

Most systems can export CSV, but modern applications, APIs and NoSQL databases expect JSON. This tool parses CSV the way spreadsheet programs write it: fields may be wrapped in double quotes, quotes inside a field are doubled (""), and a quoted field may contain commas or even line breaks. The first row becomes the property names of every object.

The delimiter is detected automatically by checking which of comma, semicolon, tab and pipe produces a consistent number of columns, so files exported from European versions of Excel (which use semicolons) work without any setup. With Convert numbers & booleans enabled, 42 becomes a number and true becomes a boolean. Values that would lose information as numbers — such as phone numbers or IDs with leading zeros like 007, or integers too large for JavaScript — stay as strings.

How to use it

1. Paste CSV text, drop a .csv/.tsv file on the input, or click Upload.
2. Leave the delimiter on Auto-detect or choose one explicitly.
3. Untick First row is header if your file has no header; you will get an array of arrays instead.
4. Use the Table tab to check that columns were split correctly, then copy or download the JSON.

Example

id,name,active
1,"Smith, Jane",true
2,Raj,false

[
  { "id": 1, "name": "Smith, Jane", "active": true },
  { "id": 2, "name": "Raj", "active": false }
]

Tips for clean results

• Empty header cells are named column_1, column_2, … and duplicate header names get a numeric suffix so no data is overwritten.
• Rows with more cells than the header keep the extra values as column_N properties.
• Blank lines are ignored.
• Turn off type conversion when every value must remain a string (for example postal codes).