JSON ↔ CSV Converter — Free Online + Custom Delimiter
Bidirectional JSON ↔ CSV conversion with 4 delimiters (comma, semicolon, tab, pipe). Supports nested objects, arrays, dynamic typing (auto-cast numbers). Uses papaparse — the npm CSV standard.
Why use this tool
JSON array → CSV table for Excel/Sheets, or CSV export → JSON for API/DB import.
Comma (CSV standard), Semicolon (EU Excel), Tab (TSV), Pipe (legacy logs). Auto-detected on parse.
CSV / JSON data may contain sensitive customer info. 100% processed in-browser, no upload.
How to use
- 1Pick direction: JSON → CSV or CSV → JSON.
- 2Pick delimiter (comma default).
- 3Paste data → click Convert.
- 41-click copy output.
JSON ↔ CSV — When to use
CSV remains the most common format for business data exchange between systems: Excel/Sheets export, database COPY, BI tool import, accounting software, payroll. JSON is the standard for web APIs / NoSQL / structured logs. Converting between the two is a frequent task for data engineers / backend devs.
Tool uses papaparse — 12K+ stars on GitHub, the foundation of countless data tools. Supports: header row, dynamic typing (Number / Boolean auto-cast), quoted strings with embedded delimiters, escape character. Streaming for huge files — but the web tool is in-memory per paste.
- ✓JSON ↔ CSV bidirectional
- ✓Comma / Semicolon / Tab / Pipe
- ✓Header auto-detect
- ✓Dynamic type cast
- ✓Quoted strings + escape
- ✓100% client-side
FAQ
How are nested JSON objects converted to CSV?
Nested objects/arrays are stringified as JSON inside the cell. Flat structure (array of primitive-valued objects) is the best fit.
CSV with quoted fields containing commas?
Yes. The tool parses quoted strings correctly: '"Smith, John"' stays in a single field.
Export directly to Excel?
Phase 1 outputs CSV text only. xlsx export needs a heavier lib (~1MB), deferred Phase 2. For now, paste CSV into Excel — works fine.