CSV to JSON Converter

Convert CSV (or data pasted from Excel or Google Sheets) to JSON, and JSON back to CSV. It detects the delimiter automatically, handles quoted fields, converts numbers and true/false values, flattens nested JSON, and shows a table preview.

Tips

  • From Excel or Google Sheets: select the cells, copy and paste them here. They paste as tab-separated values, which are detected automatically.
  • Header row: when on, the first row gives the property names (“array of objects”). When off, you get an array of arrays.
  • Nested JSON → CSV: nested objects become dotted column names such as address.city, and arrays are joined with “; ”.
  • Fields containing commas, quotes or line breaks are quoted correctly (RFC 4180), so the CSV opens cleanly in Excel.

Frequently asked questions

Why do my numbers lose leading zeros?

With “Convert numbers” on, 00123 becomes 123. Turn it off to keep PIN codes, phone numbers and IDs as text.