CSV to JSON Converter guide
Convert comma-, semicolon-, or tab-delimited rows into a formatted JSON array of records.
What this tool does
CSV to JSON parses delimited text one character at a time so common quoted-field rules are handled correctly. A quoted cell may contain the selected delimiter or a line break, and two quotation marks inside a quoted cell are converted to one literal quotation mark. Both Unix and Windows line endings are accepted.
When the first-row header option is enabled, each header becomes a JSON field name. Blank header cells receive generated names such as column_2, while duplicate field names are rejected because duplicate object keys would make the conversion ambiguous. When no header is supplied, the tool creates column_1, column_2, and additional names based on the widest row.
Every cell is deliberately preserved as a JSON string. Values such as 0017, false, 2026-08-03, and long account identifiers are not guessed as numbers, booleans, or dates. This protects their written form, but it means a downstream schema must perform any required type conversion.
How to use it
- Paste the source CSV or other supported delimited text.
- Choose comma, semicolon, or tab to match the source.
- Indicate whether the first row contains field names.
- Select Convert CSV to JSON.
- Review the record and field counts, then copy or download the formatted JSON.
Compare several records with the source before importing the result elsewhere. If a row contains more fields than the header, the tool stops with an error instead of silently discarding values. Uneven shorter rows receive empty strings for missing cells.
Benefits
- Supports quoted delimiters and multiline values
- Handles doubled quotation marks in quoted fields
- Rejects duplicate headers and extra unnamed fields
- Preserves identifiers and leading zeros as strings
- Converts and downloads entirely in the browser
Data quality and safety
CSV is not one perfectly uniform standard. Some exports use alternative encodings, unusual escape conventions, comments, or multi-character delimiters that this converter does not support. If pasted text appears garbled, reopen the source with the correct encoding and copy valid Unicode text.
JSON output can still contain untrusted content. Validate fields before placing them into HTML, database queries, commands, or automated workflows. Conversion changes the container format; it does not sanitize, verify, or grant permission to use the underlying data.
Practical notice: Review the schema, privacy requirements, and untrusted values before using converted data in another system.