How to Convert CSV to JSON Online
Transform CSV spreadsheet data to JSON format instantly in your browser. Free, private, no upload needed.
CSV (Comma-Separated Values) is the standard format for spreadsheet exports and data interchange. JSON (JavaScript Object Notation) is the standard for web APIs and modern applications. Converting between them is a daily task for developers and data analysts.
ConvertCraft's Data Converter handles CSV to JSON conversion entirely in your browser. Your data stays on your device — ideal for sensitive datasets like customer records or financial exports.
To convert: open the Data Converter tool, paste or drop your CSV file, preview the parsed data, and click Convert to JSON. The tool auto-detects delimiters (comma, semicolon, tab) and handles quoted fields correctly.
The output JSON follows a standard array-of-objects structure where each row becomes an object and column headers become property keys. You can also choose a nested structure for hierarchical data.
For large datasets with thousands of rows, the converter uses streaming parsing to avoid memory issues. Files up to 50MB can be converted without problems on modern devices.
Frequently Asked Questions
How are CSV column headers handled?
The first row of the CSV is treated as column headers. Each subsequent row becomes a JSON object with those headers as property keys.
What about special characters in CSV data?
The parser handles quoted fields, escaped commas, newlines within fields, and Unicode characters correctly according to RFC 4180.
Can I convert JSON back to CSV?
Yes. The Data Converter supports bidirectional conversion — CSV to JSON and JSON to CSV are both available in the same tool.