CSV to JSON Converter

About the CSV to JSON Converter

This tool converts CSV into a JSON array of objects, and JSON back into CSV. The parser follows RFC 4180 quoting: fields wrapped in double quotes can contain the delimiter, line breaks, and doubled quotes ("") for a literal quote. You can choose comma, semicolon, tab or pipe as the delimiter; TSV files and many European Excel exports need tab or semicolon.

With First row is header on, the first row supplies the object keys; empty or missing headers become column1, column2 and so on. Detect numbers and booleans turns 42, 3.5, true, false and null into real JSON types, while values with leading zeros such as ZIP codes stay strings. A preview table shows the first 100 rows. Conversion runs in your browser, so exports with customer data never leave your machine.

How to use it

1. Pick a direction: CSV → JSON or JSON → CSV.
2. Paste your data, or click Load sample.
3. Set the delimiter and header options.
4. Copy the output or download it as data.json or data.csv.

Examples

• Convert a small CSV export: produces two objects with numeric id and boolean active.
• Turn a JSON array into CSV: input starting with [ switches to JSON → CSV, and Alan, T. is quoted.

Common questions

How are nested objects handled in JSON to CSV?

Columns are the union of all top-level keys. Nested objects and arrays are written as JSON strings in a single cell.

Why do I get "Unterminated quoted field"?

A field opened with " was never closed. Check for a stray quote, or a quote inside a field that wasn't doubled.

What input does JSON to CSV expect?

An array of objects. A single object is treated as one row; anything else gives "Expected an array of objects".

Related tools

• JSON Formatter & Validator: inspect or sort the converted JSON.
• Test Data Generator: create sample rows to convert.
• Text Diff Checker: compare two exports.