CSV to JSON Converter

About CSV to JSON Converter

CSV to JSON Converter is a free online tool that converts CSV (Comma-Separated Values) files into JSON (JavaScript Object Notation) format. Upload a CSV file or paste CSV data, choose your output format, and download the converted JSON file—all processed locally in your browser for complete privacy.

Why convert CSV to JSON?

JSON is the standard data format for web APIs and modern applications. Converting CSV to JSON makes your data ready for:

- Web application development
- API requests and responses
- JavaScript data processing
- NoSQL databases (MongoDB, CouchDB)
- Mobile app data storage

JSON provides better structure for nested data and is more flexible than CSV for complex data types.

What output formats are available?

This tool supports two JSON output formats:

1. Array of Objects (Recommended): Each CSV row becomes a JSON object with headers as keys. Perfect for most use cases, especially when working with databases or APIs.
Example: [{"name": "John", "age": 30}, {"name": "Jane", "age": 25}]

2. Array of Arrays: Each CSV row becomes a JSON array. Useful when you need a simple matrix format or want to preserve the exact CSV structure.
Example: [["John", 30], ["Jane", 25]]

Does my data leave my device?

No. All CSV to JSON conversion happens entirely in your browser using JavaScript. Your data never leaves your machine, ensuring complete privacy for sensitive information like customer data, financial records, or confidential reports.

What delimiters are supported?

The tool supports common CSV delimiters:
- Comma (,) - Standard CSV format
- Semicolon (;) - Common in European locales
- Tab (\t) - TSV format
- Pipe (|) - Alternative delimiter
- Custom - Specify any character

You can also use Auto-detect to let the tool determine the delimiter automatically based on your data.

Can I minify the JSON output?

Yes. Enable the 'Minify JSON' option to remove all unnecessary whitespace and line breaks, creating the smallest possible JSON file. Minified JSON is ideal for:
- Reducing file size for storage
- Faster network transmission
- Production environments
- API responses

If you need human-readable JSON, keep minify disabled and choose your preferred indent size (2, 4, or 8 spaces).

What if my CSV doesn't have headers?

If your CSV file doesn't have a header row, uncheck 'First row is header'. The tool will:
- For Array of Objects: Generate default keys like "column_1", "column_2", etc.
- For Array of Arrays: Use the data directly without keys

You can then edit the JSON output or add custom keys as needed.