CSV to JSON Converter
Convert CSV to JSON online. Auto-detects delimiters, parses headers into object keys, and coerces numbers and booleans.
How it works
CSV sits at the boundary between spreadsheets and code. It is plain text, trivially human-editable, but notoriously inconsistent: delimiters vary, quoting rules get bent, and line endings differ between operating systems. Converting CSV to JSON is usually the first step in any data pipeline written in JavaScript, Python, or Go.
This converter uses PapaParse with header detection and dynamic type inference enabled. The first row is treated as field names, so each subsequent row becomes an object keyed by column name. PapaParse auto-detects the delimiter by sampling the first few lines — it handles commas, tabs, semicolons (common in European locales), and pipes.
Dynamic typing converts numeric-looking strings into JSON numbers and `"true"`/`"false"` into booleans. Everything else stays as a string, including ISO timestamps (you can post-process those yourself). Rows with mismatched column counts produce a parse error that is surfaced in the output panel. If your CSV uses a custom escape character or non-UTF-8 encoding, decode it to UTF-8 text first before pasting.
Frequently asked questions
- What delimiters are supported?
- The parser auto-detects commas, semicolons, tabs, and pipes based on frequency in the header row.
- Are numbers and booleans preserved as JSON types?
- Yes. Values that look like numbers (123, 3.14) become JSON numbers, and "true"/"false" become booleans. Everything else stays a string.
- What if my CSV has no header?
- Add a header row manually, or the output will use generic keys like Column1, Column2. Most real-world CSVs have a header.
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