CSV ↔ JSON Converter
Convert between CSV and JSON with delimiter controls and auto-flattening
About CSV ↔ JSON Converter
How CSV ↔ JSON Converter Works
Parses Comma-Separated Values compliant with IETF RFC 4180 and JSON arrays compliant with RFC 8259. Handles embedded quotes, multi-line fields, custom delimiters (comma, semicolon, tab, pipe), and nested object flattening client-side with 0 server network requests.
CSV ↔ JSON Converter enables fast, bidirectional transformation between tabular Comma-Separated Values and structured JSON arrays. Fully compliant with RFC 4180, it handles nested object flattening with dot notation, custom delimiter configuration, and automatic primitive type casting.
Frequently asked questions
Is my CSV or JSON data uploaded to a server?+
No. The conversion, parsing, and file generation run 100% inside your browser using client-side JavaScript. No spreadsheet or JSON data ever leaves your device.
Does this tool support tab-separated (TSV) or semicolon-separated files?+
Yes. Use the Delimiter dropdown to choose between Comma (,), Semicolon (;), Tab (\t), or Pipe (|).
How are nested JSON objects converted to CSV?+
Nested objects are automatically flattened into dot notation headers (e.g. user.address.city). You can also disable flattening to serialize nested objects as JSON strings.
Does it preserve numbers and boolean types?+
Yes. When converting CSV to JSON, numeric values ('100', '49.99') and booleans ('true', 'false') are automatically cast to native JavaScript numbers and booleans.
Limitations
Extremely massive CSV files exceeding hundreds of megabytes may encounter browser memory limits; for typical files up to tens of thousands of rows, execution is instantaneous.