JSON ↔ CSV Converter

How to Use

JSON to CSV

1. Paste a JSON array of objects into the JSON input box on the left.
2. Click Convert to CSV. The tool will use object keys as CSV headers and show a read-only preview on the right.
3. Click the download button (⬇️) to save the CSV result as a file.

CSV to JSON

1. Click Choose file and select a CSV file from your computer.
2. Click Convert to JSON. The first row is treated as headers, and each following row becomes a JSON object.
3. The JSON array is shown as a read-only preview on the right. Use the download button (⬇️) to save it as a JSON file.

This tool is designed for simple conversions between JSON arrays of objects and CSV files with a header row. Nested values are serialized as JSON strings. All conversions run locally in your browser; no data is uploaded or stored on a server.

Technical notes

JSON parsing uses the browser's native JSON.parse and JSON.stringify. CSV parsing supports quoted fields, embedded commas, and newlines within quoted text. Files are processed as plain text in the browser using the FileReader API, and download links are generated dynamically using Blob objects. This allows conversions without sending your data to any backend service.