Free Online CSV to JSON Converter
Convert CSV data to a JSON array instantly. Choose your delimiter, paste your CSV, and get clean JSON output with headers as keys.
How the CSV to JSON Converter Works
This tool takes CSV (Comma-Separated Values) data and converts it into a JSON array of objects. The first row is treated as headers, which become the keys in each JSON object. Subsequent rows become the values. The tool supports quoted fields containing commas and handles common CSV formatting edge cases.
Supported Delimiters
While CSV traditionally uses commas, many datasets use different delimiters. This tool supports comma, semicolon, and tab delimiters. Semicolons are common in European locales where commas are used as decimal separators. Tab-delimited data (TSV) is exported by many spreadsheet applications and databases.
Working with the JSON Output
The JSON output is an array of objects where each object represents one row. The output is formatted with indentation for readability. You can copy it directly for use in JavaScript applications, API testing, database imports, or configuration files. The JSON is valid and can be parsed by any JSON-compliant parser.
Frequently Asked Questions
Does the first row need to be headers?
Yes. This converter uses the first row as object keys for the JSON output. Each subsequent row becomes an object with those keys. If your CSV lacks headers, add them manually before converting.
How does it handle quoted fields?
The parser correctly handles double-quoted fields. Commas inside quoted fields are treated as data, not delimiters. Double quotes within a quoted field are escaped as two consecutive double quotes.
Is there a size limit?
Since all processing happens in your browser, the limit depends on your device's available memory. For most modern devices, CSV files up to several megabytes work well. Very large files may cause the browser to slow down.
Does it preserve data types?
All values are output as strings in the JSON. If you need numeric types, you can post-process the JSON to convert numeric strings to numbers in your application code.
Is my data sent to a server?
No. All conversion happens entirely in your browser using JavaScript. Your CSV data never leaves your device.