What happens if my CSV has no header row?

The converter uses column indices as JSON keys (column_0, column_1). Add a header row for meaningful JSON keys.

Can I convert JSON with nested objects to CSV?

Nested objects cannot be directly represented in flat CSV. The converter flattens top-level keys. Deeply nested structures may require manual flattening.

What delimiter should I use?

Default is comma for standard CSV. Use semicolon for European locales. Use tab (TSV) for data with both commas and semicolons.

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CSV ↔ JSON Converter

Convert between CSV and JSON instantly. Handles quoted fields, custom delimiters, nested data, and more — everything runs in your browser.

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CSV Input

Delimiter

Header row

Trim spaces

Skip empty

JSON Output

How to use

Pick a direction (CSV → JSON or JSON → CSV) and paste your data into the input panel.
Adjust the delimiter, header, and quoting options to match your data.
Copy the converted output or download it as a .json or .csv file.

FAQ

Fields wrapped in double quotes are parsed as a single value, even if they contain commas or newlines. Escaped quotes inside ("") are converted to a single ". Output that contains the delimiter, a quote, or a newline is automatically quoted on the JSON → CSV side.

The tool supports comma, semicolon, tab, and pipe. CSV → JSON also has an Auto mode that samples your input to pick the most likely delimiter. Use semicolon for European locales or tab (TSV) for data that may contain both commas and semicolons.

Everything runs in your browser, so the upper limit is your device's memory. A few MB of CSV is typically fine; tens of MB may freeze the page during parsing. For very large datasets, split the file into chunks or use a streaming parser locally.