CSV to JSON Converter

Example: CSV input and real JSON output

The output below was generated by the same conversion code the converter uses, run on this sample when the page was built.

sku,name,price,stock
SKU-104,USB-C cable,9.99,240
SKU-221,Laptop stand,34.5,58
SKU-310,Webcam cover,3.25,1200
SKU-415,Desk mat,19,0

[
  {
    "sku": "SKU-104",
    "name": "USB-C cable",
    "price": 9.99,
    "stock": 240
  },
  {
    "sku": "SKU-221",
    "name": "Laptop stand",
    "price": 34.5,
    "stock": 58
  },
  {
    "sku": "SKU-310",
    "name": "Webcam cover",
    "price": 3.25,
    "stock": 1200
  },
  {
    "sku": "SKU-415",
    "name": "Desk mat",
    "price": 19,
    "stock": 0
  }
]

JSON output is 176% larger than the CSV input. The same data is 252 characters as minified JSON and 373 as pretty-printed JSON. Sizes are character counts, not tokens: token counts depend on the model's tokenizer (see the tokenizer comparison).

CSV to JSON: what changes

• Every value in the JSON is a string, including prices and stock counts. Cast the columns you need as numbers or booleans after converting.
• Reading CSV: CSV has no types: every cell is read as a string, so 9.99 becomes "9.99" in the output (visible in the sample below). The first row must be the header, and nested data cannot be represented.
• Writing JSON: Output is pretty-printed with your chosen indentation. JSON is the safest target when the data goes into code, an API, or another tool.

Why Convert CSV to JSON?

Use JSON when you need maximum compatibility with other systems, APIs, or programming languages. It's the de facto standard for web APIs and data exchange.