CSV ↔ JSON Converter
Convert CSV spreadsheets to JSON arrays and back. Handles quoted fields, numbers and booleans.
CSV (Comma-Separated Values) is the universal format for spreadsheet data — exported from Excel, Google Sheets, databases, and reporting tools. JSON is the universal format for web APIs. Converting between them is a constant need: loading spreadsheet data into a web application, exporting API data to Excel, or preparing datasets for data science tools. This bidirectional CSV ↔ JSON converter handles the conversion instantly with proper support for quoted fields and type detection.
📋 How to Use This Calculator
Choose the conversion direction with the toggle. For CSV to JSON: paste CSV with a header row as the first line — the headers become object keys. Rows become objects in a JSON array. Numbers and booleans are automatically detected (a value of 30 becomes the number 30, not the string "30"). For JSON to CSV: paste a JSON array of objects. The first row of the output will be the header (all unique keys), followed by data rows. Fields containing commas or double quotes are automatically wrapped in double quotes per RFC 4180.
💡 Key Facts & Information
CSV format follows RFC 4180: fields separated by commas, rows separated by CRLF or LF, values with commas or double quotes wrapped in double quotes, and double quotes inside quoted fields escaped by doubling them (""). This converter handles all these cases correctly. Type inference converts numeric strings to numbers and "true"/"false" to booleans — if you want to preserve all values as strings, review the JSON output and adjust as needed. For very large CSV files (millions of rows), browser memory limits apply; use server-side tools like pandas (Python) or csv-parser (Node.js) for bulk processing.