CSV to JSON Converter Online

What Is a CSV to JSON Converter?

A CSV to JSON converter parses comma-separated values data and transforms it into JavaScript Object Notation format. CSV files are ubiquitous in data workflows — exported from spreadsheets, databases, CRM systems, and analytics platforms. JSON is the standard format consumed by REST APIs, JavaScript applications, NoSQL databases like MongoDB, and data visualization libraries.

This converter reads CSV input, uses the first row as column headers to create object keys, and maps each subsequent row into a JSON object. It properly handles quoted fields with embedded commas, escaped double quotes, and multiline values per RFC 4180. The conversion executes entirely within your browser using client-side JavaScript, ensuring your spreadsheet data containing customer records, financial figures, or internal metrics never reaches an external server.

How to Convert CSV to JSON

1. Paste your CSV data into the input panel. The first row should contain column headers that will become JSON object keys.
2. Click Convert to parse the CSV and generate a JSON array where each row becomes an object with header-based keys.
3. Review the structured JSON in the output panel. Each row from your CSV is now a JSON object with named properties matching your column headers.
4. Copy or download the JSON array for importing into MongoDB, sending to a REST API, or using in your JavaScript application.

Why Convert CSV to JSON with PinusX?

When migrating data from spreadsheets to modern applications, CSV to JSON conversion is one of the most frequent operations developers perform. PinusX handles this conversion with 100% client-side processing, meaning your CSV data stays in your browser and is never uploaded to remote servers. This is especially important when working with exported customer databases, employee records, or financial reports. The November 2025 incident where jsonformatter.org leaked 80,000 credentials demonstrated the real-world risks of processing sensitive data through server-side tools. With PinusX, that risk is eliminated entirely.

Frequently Asked Questions

Does the converter handle commas inside CSV fields?

Yes. Fields wrapped in double quotes can contain commas, newlines, and other special characters. The parser follows RFC 4180 rules, so quoted fields are handled correctly. For example, the field "New York, NY" is treated as a single value, not split into two columns.

Can I use semicolons or tabs instead of commas?

This converter uses commas as the default delimiter. For tab-separated values, use our dedicated TSV to JSON converter. If you have semicolon-delimited data, you can preprocess it by replacing semicolons with commas before pasting.

What if my CSV has no header row?

If your CSV lacks a header row, the converter will use the first data row as headers, which may produce unexpected key names. In that case, consider adding a header row manually before converting, or use a tool that supports headerless CSV conversion.

How does it handle empty cells in the CSV?

Empty cells are preserved as empty strings in the JSON output. A row like 'Alice,,30' where the middle field is empty will produce an object with an empty string value for the corresponding key.

Is my uploaded CSV data stored anywhere?

No data is uploaded or stored. The entire conversion runs locally in your browser. No network requests are made during processing, and no cookies or local storage entries are created with your data. Your CSV content exists only in your browser's memory while the page is open.

Your data never leaves your browser. 100% client-side processing.