JSON ↔ CSV ↔ Excel Converter
Convert between JSON, CSV, and Excel formats. Auto-detects your input format. Preview data as a table. Everything runs in your browser — your files never leave your device.
Delimiter:Empty values:
Input
Drop a JSON, CSV, or Excel file
Or paste text below
Output will appear here
Frequently Asked Questions
- Which formats can I convert between?
- All three directions are supported: JSON → CSV, JSON → Excel, CSV → JSON, CSV → Excel, Excel → JSON, and Excel → CSV.
- Does it auto-detect my input format?
- Yes — paste or upload any file and the tool automatically detects whether it is JSON, CSV, or Excel based on content and file extension.
- Can it handle nested JSON?
- Yes. Enable the 'Flatten nested JSON' option and nested objects are flattened using dot notation — for example { user: { name: 'Alice' } } becomes a column named 'user.name'.
- Which Excel files are supported?
- The tool reads and writes .xlsx files (Excel 2007 and later). Legacy .xls files can also be uploaded for reading.
- Is there a row limit?
- No hard limit — all processing runs in your browser using WebAssembly and JavaScript. Very large files (100,000+ rows) may be slow depending on your device.
- How do I change the CSV delimiter?
- Use the Delimiter buttons at the top of the tool to switch between comma, semicolon, tab, and pipe separators. The output updates instantly.
- Is this tool free?
- Yes, 100% free. No account needed, no file size limits enforced by us, no data uploaded to any server.
- Does it work on mobile?
- Yes, the tool works on all modern browsers including Chrome, Firefox, Safari, and Edge on both desktop and mobile.