CSV ↔ JSON Converter
Convert CSV data to JSON arrays and objects, or transform JSON back to CSV. Handles headers, nested values, and custom delimiters. All processing happens in your browser.
Features
Bidirectional Conversion
Convert CSV to JSON and JSON to CSV with a single click. Swap input and output instantly.
Header Support
Use the first row as object keys when converting CSV to JSON for structured output.
Custom Delimiters
Support for comma, semicolon, tab, and pipe delimiters to handle different CSV formats.
Quote Handling
Properly handles quoted fields, escaped quotes, and fields containing delimiters.
Copy & Download
One-click copy to clipboard or download the result as a .json or .csv file.
100% Client-side
All conversion runs in your browser. No data is ever sent to a server.
About CSV and JSON Conversion
CSV (Comma-Separated Values) and JSON (JavaScript Object Notation) are two of the most common data interchange formats. CSV is widely used in spreadsheets, databases, and data exports because of its simplicity and human readability. JSON has become the standard for web APIs and modern application data due to its structured, hierarchical format that maps naturally to programming language objects.
Converting between these formats is a daily task for developers, data analysts, and anyone who works with structured data. Our tool handles the nuances of each format: quoted fields, escaped characters, custom delimiters, and header-based key mapping. When converting CSV to JSON, the first row can be used as object keys, producing clean array-of-objects output. When converting JSON to CSV, all unique keys across all objects are collected as headers.
Everything runs entirely in your browser using JavaScript. There are no file size limits, no server uploads, and no registration required. Whether you need to transform a small dataset or process a large CSV export, the conversion happens instantly and privately.
Frequently Asked Questions
What CSV delimiters are supported?▼
The tool supports comma (,), semicolon (;), tab, and pipe (|) delimiters. This covers the most common CSV formats from Excel, Google Sheets, and database exports.
How does the header option work?▼
When 'First row as headers' is enabled, the first row of your CSV is used as the property names for each JSON object. Without headers, the output is a simple array of arrays.
Can I convert nested JSON to CSV?▼
Nested objects are converted to their JSON string representation in the CSV output. For flat JSON arrays (objects with simple key-value pairs), the conversion produces clean CSV with proper headers.
Is my data safe when using this tool?▼
Yes. All conversion is performed entirely in your browser using JavaScript. Your data is never uploaded to any server or stored anywhere.
What happens with empty or missing fields?▼
Empty CSV fields become empty strings in JSON. When converting JSON to CSV, missing fields in some objects are left as empty cells in the CSV output.