CSV ↔ JSON Converter

RFC 4180 parser with auto-detected delimiter

🔒 This tool runs entirely in your browser — your data never leaves your device.

CSV ↔ JSON Converter

Parse CSV (or TSV / semicolon-delimited) data into JSON arrays of objects, or serialise a JSON array back to CSV. Auto-detects delimiter, supports quoted fields with embedded commas, line breaks and double-quote escapes per RFC 4180.

  • Auto-detects comma / tab / semicolon delimiter
  • RFC 4180 quoting
  • Handles embedded line breaks in quoted fields
  • Header row as JSON keys
  • Key union for differently-shaped objects
  • Runs locally

FAQ

How does delimiter auto-detection work?

We sample the first 4 KB and pick the most frequent of comma, tab, semicolon and pipe.

Does it support nested JSON in CSV cells?

On JSON → CSV, nested objects and arrays are stringified as JSON inside the cell.