KMMR Online Tools

JSON Conversion

JSON to CSV Converter

Browser-based JSON to CSV converter with direct download. Arrays of objects become rows, and nested keys are flattened with dot notation.

Record rows

Convert arrays of objects into one CSV row per item.

Flatten nested keys

Nested objects become columns such as user.name.

Download CSV

Save the converted result directly as a UTF-8 CSV file.

Need to clean up or validate the JSON first? JSON Formatter / Validator

Conversion runs in your browser

This page does not send your JSON text or key names to the server, and the conversion itself runs in the current browser. For product analytics, it sends only anonymous metadata such as size bucket, conversion mode, and row or column counts.

Conversion rules

CSV is table-shaped, so ambiguous patterns follow these fixed rules.

  • If the root value is an array of objects, each object becomes one CSV row.
  • If the root value is a single object, it becomes a one-row CSV.
  • Nested objects are flattened into column names such as user.name.
  • Arrays of scalar values become "a | b | c" or stay as JSON text. Other arrays stay as JSON text in a single cell.
  • If an API response wraps the records inside items or data, paste that array itself for the cleanest CSV output.

Input JSON

0 chars / 0 bytes

Output CSV

0 chars / 0 bytes

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