Does it handle quoted fields with commas inside?

Yes. The parser follows RFC 4180, so quoted fields, escaped double quotes ("") and line breaks inside quoted values are all handled correctly.

What does "infer numbers and booleans" do?

When enabled, clean numeric values become JSON numbers and the words true/false/null become their JSON equivalents. Turn it off to keep every value as a string.

Is my CSV uploaded anywhere?

No. Parsing happens entirely in your browser with JavaScript — your data never leaves your device.

Does the first row have to be a header?

Yes. The first row supplies the object keys for every record below it, so each subsequent row becomes one JSON object whose property names come from the header.

Can it parse tab-separated (TSV) or semicolon files?

Yes. Choose tab, semicolon or pipe as the delimiter instead of comma. European exports that use semicolons and spreadsheet TSV both convert correctly.

What happens if a row has fewer columns than the header?

Missing cells become empty strings (or empty values) in the resulting object, so every object still has the full set of keys from the header row.

Why is a number like 007 kept as a string?

Inference only converts clean numeric literals, and 007 would lose its leading zeros as a number, so it is kept as text. Turn off "infer numbers and booleans" to keep every field as a string, including phone numbers and IDs.

CSV to JSON Converter

Convert CSV to JSON in your browser

This tool turns a CSV file with a header row into a clean JSON array of objects — one object per row, keyed by the column names. It is built for developers loading spreadsheet exports into an app or API, and for anyone moving data from Excel or Google Sheets into a JSON-based system without writing a script.

How it works

The parser implements the RFC 4180 standard rather than a naive split on commas. It reads the text character by character, tracking whether it is inside a quoted field, so commas, line breaks and doubled quotes ("") inside a quoted value are preserved instead of breaking the row. The first row becomes the header; each later row is zipped against it to build an object. With “infer numbers and booleans” on, clean numeric literals become JSON numbers and the words true, false and null become their JSON equivalents — everything else stays a string.

Example

This CSV:

name,role,active
Ada,Engineer,true
"Bao, Jr.",Designer,false

becomes:

[
  { "name": "Ada", "role": "Engineer", "active": true },
  { "name": "Bao, Jr.", "role": "Designer", "active": false }
]

Note the comma inside "Bao, Jr." is kept because it is quoted. Everything runs locally in your browser — nothing is uploaded, which makes it safe for confidential spreadsheets and exports.