Paste CSV or JSON below. Nothing is uploaded — the conversion happens locally in your browser.
Input
Output
How it works
CSV to JSON parses each line by hand (respecting quoted fields with embedded commas), then guesses each value's type — numeric-looking strings become real numbers. JSON to CSV takes the reverse path: it collects the union of every key across all objects to build a consistent header row, quoting any field that itself contains a comma, quote, or newline.
FAQ
Why did my number-looking values change type in the JSON output?
CSV to JSON auto-detects values that look numeric and converts them to actual numbers rather than text — so "29" becomes 29, which matters if you need to preserve leading zeros or exact string formatting.
What happens if my CSV rows have different numbers of columns?
JSON to CSV builds one header row from the union of every key found across all the objects in your JSON — rows missing a given key just get an empty cell in that column, so ragged data doesn't break the header alignment.
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