CSV to JSON Converter

Convert CSV (Comma-Separated Values) data to JSON (JavaScript Object Notation) format instantly in your browser. This free online tool handles all CSV edge cases including quoted fields, embedded commas, newlines within quotes, and custom delimiters. No data leaves your device — all conversion happens client-side.

How to Convert CSV to JSON

• Paste your CSV data into the input textarea, or use the Upload CSV button to load a file.
• Choose your delimiter (comma, tab, semicolon, or pipe).
• Toggle Header row if your first row contains column names.
• Select output format: Array of objects (key-value pairs) or Array of arrays.
• The JSON output updates automatically as you type. Use Copy or Download JSON to save the result.

JSON to CSV Conversion

Switch to the JSON → CSV tab to convert JSON arrays back to CSV. The tool detects keys from the first object and writes them as headers, then serializes each row. Values containing commas, quotes, or newlines are automatically quoted per RFC 4180.

Supported CSV Edge Cases

• Quoted fields: "hello, world" is treated as a single field.
• Escaped quotes: Double quotes inside fields are handled ("" → ").
• Newlines in quotes: Multi-line fields wrapped in quotes are preserved.
• Custom delimiters: Tab-separated (TSV), semicolon, and pipe-delimited files are supported.

When to Use CSV vs JSON

CSV is ideal for spreadsheet data, database imports, and tabular datasets. JSON is preferred by APIs, web applications, and NoSQL databases. Converting between the two formats is common when moving data between spreadsheets and web services, preparing config files, or feeding data into JavaScript applications.

Privacy & Security

All conversion is performed entirely in your browser using vanilla JavaScript. Your data is never sent to any server, making this tool safe for sensitive or confidential information.