Free Online JSON to CSV Converter
Drop any .json, .jsonl, or .ndjson file to convert JSON into clean, standard UTF-8 CSV spreadsheets in seconds with zero server file uploads.
Key Features & Client-Side Capabilities
- RFC 4180 Compliant CSV: Properly escapes quotes, handles nested objects, and ensures clean UTF-8 comma-separated text.
- Zero Cloud Storage or Egress: All JSON parsing, flattening, and conversion runs locally in browser WebAssembly memory.
- Streams Large JSON & NDJSON: Powered by DuckDB read_json_auto for blazing-fast handling of large files.
Frequently Asked Questions
How do I convert JSON to CSV without uploading to an external server?
Drop your .json or .jsonl file onto TableView above and click "Export CSV". The file is parsed locally in your browser tab using WebAssembly and saved directly to your computer.
Can this tool convert JSON Lines (NDJSON) to CSV?
Yes! Both standard hierarchical JSON arrays and newline-delimited JSON Lines (NDJSON/JSONL) are automatically detected and converted into tabular CSV.
What happens to nested JSON objects and arrays?
DuckDB automatically flattens first-level scalar attributes and serializes nested objects and lists into structured text columns.