Convert CSV to JSON and JSON to CSV instantly. Paste text or upload files. Live preview, table view, format options — all in your browser.
Your data never leaves your device — all conversion is 100% local in your browser
CSV Input
Upload CSV file
CSV, TXT
Error
CONVERT
JSON Output
Converted successfully
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Table Preview
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Frequently Asked Questions
Is my data uploaded to a server?
Never. All conversion happens entirely in your browser using JavaScript. Your CSV or JSON data never leaves your device — no upload, no server, nothing stored anywhere.
What CSV formats are supported?
Standard comma-separated CSV, semicolon-separated (common in European locales), tab-separated (TSV), and pipe-separated formats. Select your delimiter in the settings row above the editor.
What JSON structure does CSV→JSON produce?
An array of objects where each object represents one CSV row, and each key is a column header. Example: [{"name":"Alice","age":30},{"name":"Bob","age":25}]. If "Header row" is off, keys become col_0, col_1, etc.
What JSON structure does JSON→CSV accept?
An array of objects (most common API format). Each object becomes a CSV row. Keys from the first object are used as column headers. Enable "Flatten nested" to handle objects within objects — nested keys become dot-notation columns like "address.city".
Can I upload a file instead of pasting?
Yes. Click "Upload CSV file" (or "Upload JSON file" in JSON→CSV mode) to load a file directly from your device. The file is read locally — it is never uploaded to any server.
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