What CSV format is supported?

The tool supports standard CSV format with headers in the first row and data in subsequent rows. Delimiters supported: comma (,), semicolon (;), or tab. CSV should have consistent columns across all rows. Standard CSV escaping (quotes for values containing delimiters) is supported.

How is the JSON structure created?

First CSV row becomes JSON object keys (headers). Each subsequent CSV row becomes a JSON object with those keys. Result is an array of objects: [{"header1": "value1", "header2": "value2"}, ...]. Each CSV row becomes one JSON object in the array.

Can I choose the delimiter?

Yes! Select delimiter: comma (,), semicolon (;), or tab. Comma is standard for most CSV files. Semicolon is common in European locales (especially Excel exports). Tab is used in TSV (tab-separated values) files. Choose the delimiter that matches your CSV file.

What happens to empty cells in CSV?

Empty cells in CSV become empty strings ("") or may be omitted in JSON objects, depending on the conversion. The tool handles empty cells appropriately. If you need null values instead of empty strings, you may need to process JSON after conversion.

Can I convert CSV with multiple sheets?

No, this tool converts single CSV data. CSV format doesn't support multiple sheets (that's an Excel feature). If you have multiple sheets, convert each sheet to CSV separately, then convert each CSV to JSON. The tool processes one CSV at a time.

How does the tool handle quoted fields with commas?

The tool correctly handles RFC 4180 compliant CSV: fields containing commas, newlines, or quotes are enclosed in double quotes. A literal double quote within a quoted field is escaped as two double quotes (""). For example, the field 'He said "hello"' would be stored as "He said ""hello""" in CSV.

Does the converter preserve data types?

Yes. The tool automatically detects and preserves data types: numbers remain as numbers (not wrapped in quotes in JSON), boolean values (true/false) are preserved, and text remains as strings. Empty fields become null values. You can preview the JSON output to verify types before downloading.

What delimiter formats are supported?

The tool auto-detects the most common delimiters: comma (,), semicolon (;), tab (\t), and pipe (|). Semicolons are common in European CSV files where commas are used as decimal separators. If auto-detection fails, you can manually specify the delimiter.

CSV to JSON Converter - Free Online Tool

When to Use This Tool

Use this when:

You need to convert CSV data to JSON format for APIs or web applications
You want to import spreadsheet data (Excel, Google Sheets) into JSON format
You're working with CSV exports and need to convert them to JSON for processing
You need to transform CSV data to JSON for API requests or data transmission
You want to convert CSV to JSON for use in JavaScript applications or databases
You're migrating data from CSV format to JSON for modern applications
You need to convert tabular data to structured JSON format

Don't use this if:

You need to convert JSON to CSV (use JSON to CSV converter)
You require complex nested JSON structures (CSV is flat, produces flat JSON)
You need to convert very large CSV files (over 10MB may process slowly)
You want to preserve CSV data types exactly (JSON may interpret types differently)
You require CSV-specific features like multiple sheets or complex formatting

What is a CSV to JSON Converter?

A CSV to JSON converter transforms CSV (Comma-Separated Values) data into structured JSON format (arrays of objects) for use in web applications, APIs, and modern data pipelines. Our converter processes everything in your browser — your data never leaves your device.

CSV to JSON conversion is essential when you need to import spreadsheet data into web applications, prepare data for REST API consumption, convert legacy data formats for modern applications, create configuration files from spreadsheet-managed data, and transform database exports for JavaScript/TypeScript processing.

This tool is valuable for developers importing spreadsheet data into applications, data engineers building data pipelines that consume CSV, full-stack developers creating API request payloads from CSV exports, product managers preparing data for application import, and analysts transforming CSV data for use in JavaScript-based visualization tools.

Compared to writing custom parsing scripts (which must handle edge cases like quoted fields, nested commas, and newlines within values), programming libraries that require a development environment, or online converters that process your data on remote servers, PureXio handles the conversion instantly in your browser with robust CSV parsing.

The tool auto-detects delimiters (comma, semicolon, tab), uses the first row as property names by default, handles quoted fields correctly, preserves data types (numbers remain numbers, not strings), and supports large CSV files. You can preview the JSON output, configure formatting (pretty-printed or minified), and download the result.

Best for: converting CSV to structured JSON arrays. Auto-detect delimiters, type preservation, quoted field handling. Preview and download. 100% private.

How to Convert CSV to JSON

Paste your CSV data into the input field. CSV should have headers in first row, followed by data rows. Select delimiter: comma, semicolon, or tab (matches your CSV format)

Click 'Convert to JSON' to convert CSV to JSON format. Tool automatically detects headers and converts each row to a JSON object. First row becomes keys, subsequent rows become values

Review the converted JSON output. Copy JSON to clipboard or download as JSON file. Use in APIs, web applications, or any JSON-compatible system

Common Use Cases

API data preparation: Convert CSV exports to JSON for API requests or data transmission

Spreadsheet to web: Convert Excel or Google Sheets data to JSON for web applications

Data import: Convert CSV data to JSON for importing into databases or applications

Data transformation: Convert CSV to JSON for JavaScript applications or frontend use

API integration: Convert CSV exports to JSON format for API integration

Data migration: Convert CSV data to JSON for modern application compatibility

Web development: Convert CSV data to JSON for use in React, Vue, or other frameworks

Features

Convert CSV data to JSON array of objects format

Automatic header detection from first CSV row

Support for custom delimiters: comma, semicolon, or tab

Each CSV row becomes a JSON object with header keys

Download converted JSON as file for use in applications

One-click copy JSON to clipboard

100% private—all processing happens in your browser

Limitations & Constraints

CSV is flat format—converts to flat JSON objects, not nested structures

All CSV values become strings in JSON—data type detection is limited

Very large CSV files (over 10MB) may process slowly—consider splitting data

CSV with inconsistent columns may produce incomplete JSON objects

Special characters or quotes in CSV may require proper escaping

Troubleshooting

CSV conversion fails or shows error

Solution: Check that CSV is properly formatted with consistent columns. Ensure first row contains headers. Verify delimiter matches your CSV format (comma, semicolon, or tab). Check for special characters or quotes that may need escaping. Ensure CSV has proper line breaks between rows. Prevention: Use standard CSV format with consistent structure.

JSON output has wrong structure or missing data

Solution: Verify CSV structure—first row should be headers, subsequent rows should be data. Ensure all rows have same number of columns. Missing values may produce empty strings or undefined in JSON. Check that delimiter is correct for your CSV. Prevention: Ensure CSV has consistent structure with headers in first row.

Wrong delimiter selected

Solution: CSV delimiters vary by region and application. Comma (,) is most common. Semicolon (;) is common in European locales. Tab is used in some exports. Check your CSV file to identify delimiter—look at how columns are separated. Select matching delimiter for correct conversion. Prevention: Identify CSV delimiter before converting.

Special characters or quotes causing issues

Solution: CSV files with special characters or quotes may need proper escaping. Standard CSV uses quotes to escape values containing delimiters. If conversion fails, check CSV for proper quote escaping. Some CSV files may have encoding issues—ensure CSV is UTF-8 encoded. Prevention: Use properly formatted CSV with correct escaping.

All values are strings in JSON

Solution: CSV stores all values as text—conversion to JSON preserves this. Numbers, dates, and booleans remain as strings in JSON. This is expected behavior. If you need typed values, parse them in your application after conversion. JSON doesn't automatically detect CSV data types. Prevention: Understand that CSV values become strings in JSON.