Private data converter
CSV to JSON Converter
Convert real-world CSV—including quoted commas, escaped quotes, and multiline fields—into predictable JSON. Values remain strings unless you explicitly enable safe type detection.
Paste CSV or upload a .csv file to begin.
Files up to 5 MB are read locally. Input content and filenames are not sent to ToolsWeave analytics.
How to convert CSV to JSON
- 1
Paste or upload CSV
Add CSV text or choose a UTF-8 .csv file up to 5 MB.
- 2
Choose CSV settings
Use automatic delimiter detection or select comma, semicolon, or tab, then confirm whether the first row contains headers.
- 3
Convert to JSON
Choose string-safe defaults or explicit type detection, and select formatted or minified output.
- 4
Copy or download JSON
Review the preview, copy the complete result, or save converted.json.
How CSV headers become JSON keys
By default, the first nonblank row supplies object keys. Blank headings become column_1-style names. Duplicate headings are renamed with numeric suffixes instead of overwriting earlier values, and the result reports that change.
CSV vs JSON
CSV stores table-shaped text while JSON can express nested data and typed values. This converter creates one object per data row. CSV values remain strings by default so identifiers such as 00123 are not silently converted to numbers.
When should you convert CSV to JSON?
JSON is often easier to consume in web applications, APIs, scripts, configuration pipelines, and document databases. Conversion is also useful when you need explicit keys for each CSV column or a formatted structure for inspection and debugging.
CSV to JSON Converter FAQ
How do I convert CSV to JSON?
Paste or upload CSV, confirm the delimiter and header settings, then select Convert to JSON.
Does the parser support quoted commas?
Yes. It handles quoted delimiters, doubled quote escapes, multiline quoted fields, CRLF and LF line endings, empty fields, Unicode, and a UTF-8 BOM.
Are numbers converted automatically?
No. Values stay strings by default, preserving identifiers such as 00123. Optional type detection converts unambiguous numbers, true, false, and null.
Which delimiters are supported?
You can select comma, semicolon, or tab. Automatic mode compares the first records and reports the detected delimiter after conversion.
What happens with duplicate headers?
Later duplicates receive suffixes such as name_2. This prevents one column from silently overwriting another.
Is my CSV uploaded?
No. The browser reads and converts CSV locally, and analytics does not receive the CSV text or filename.
Related JSON and data tools
Format JSON before conversion, validate JSON syntax, use the opposite converter to convert JSON to CSV, or browse all developer tools.