JSON to CSV Converter

Example: JSON input and real CSV output

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

[
  {
    "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
  }
]

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

CSV output is 64% smaller than the JSON 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).

JSON to CSV: what changes

• This page uses a flat array of products because CSV can only hold rows of scalar values. For nested JSON like API responses, pull out the array and flatten nested fields first (for example with a JSONPath query in JSON tools).
• Reading JSON: Input must be strict JSON: no comments, trailing commas, or single quotes. If it came from an LLM or a log file, run it through the JSON repair tool first.
• Writing CSV: CSV output needs a root-level array of flat objects; anything else fails with "CSV output requires an array of objects". Nested objects are not flattened, so extract or flatten them first.

Why Convert JSON to CSV?

Use CSV when working with spreadsheets (Excel, Google Sheets), doing data analysis, or exporting data for external use.