DEVELOPER TOOL

CSV to JSON Converter

Paste CSV or load a file and get clean JSON. Quoted fields, commas and line breaks inside values are handled correctly.

CSV data Or load a .csv or .txt file (up to 5 MB)

Delimiter

Output format

First row contains column names Trim spaces around values Convert numbers and true/false to JSON types

JSON output

How to use the CSV to JSON Converter

Paste CSV or choose a file, set the options and press Convert to JSON. With “first row contains column names” on, you get an array of objects; with it off, you get an array of arrays.

The parser follows the usual CSV rules: a value wrapped in double quotes can contain the delimiter or a line break, and a doubled quote ("") stands for a literal quote mark. Empty column names become column_N and repeated names get a number suffix.

Examples and uses

The CSV name,city / "Smith, Anna","New York" becomes [{"name": "Smith, Anna", "city": "New York"}]. The comma inside the quotes stays part of the name.

Limitations and good to know

Values stay as text unless you tick the type-conversion option. With it on, only clean numbers become numbers (so “007” and phone numbers with leading zeros stay text, and integers too large to be exact are kept as text). Everything runs in your browser, so very large files may be slow; files over 5 MB are rejected. The file is read as text in your browser’s default encoding (UTF-8 is expected).

Frequently asked questions

Is my CSV uploaded?

No. It is parsed in your browser and not sent anywhere.

What if a row has fewer or more columns than the header?

Missing values become empty strings, and extra values are added as column_N keys so no data is lost.

Can it read semicolon-separated files?

Yes. Leave delimiter on auto-detect or choose semicolon, tab or pipe.

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