swap_horiz CSV to JSON Converter

Convert CSV to JSON and JSON to CSV with type inference, multiple output formats, and data preview

menu_book Format Reference expand_more

CSV Format

name,age,active
John Doe,30,true
Jane Smith,25,false
"Bob, Jr.",35,true
  • First row typically contains headers
  • Values containing delimiters must be quoted
  • Quotes within values: use ""

JSON Array of Objects

[
  {"name": "John", "age": 30},
  {"name": "Jane", "age": 25}
]
  • Most common format for data interchange
  • Each object represents one row
  • Keys become column headers

Output Formats

Array of Objects [{...}, {...}]
Object with Keys {"id1": {...}, ...}
Column-based {"col": [...]}
Records [[...], [...]]

CSV to JSON Converter - Free Online Tool

Convert CSV (Comma Separated Values) to JSON (JavaScript Object Notation) and vice versa with our free online converter. Perfect for developers, data analysts, and anyone working with data interchange formats.

Features

  • Bidirectional conversion - Convert CSV to JSON and JSON to CSV with a single tool
  • Multiple delimiters - Support for comma, semicolon, tab, and pipe delimiters with auto-detection
  • Type inference - Automatically parse numbers, booleans, and null values
  • Multiple output formats - Array of objects, keyed objects, column-based, or raw records
  • Nested object handling - Flatten nested JSON objects with dot notation
  • Column name transformation - Convert headers to camelCase, snake_case, or other formats
  • Data preview - Visual table preview with statistics
  • File upload - Import CSV or JSON files directly
  • Client-side processing - Your data never leaves your browser

What is CSV?

CSV (Comma Separated Values) is a simple file format used to store tabular data. Each line represents a row, and columns are separated by a delimiter (typically a comma). CSV is widely used for:

  • Spreadsheet exports from Excel, Google Sheets, etc.
  • Database imports and exports
  • Data exchange between different applications
  • Simple data storage that's human-readable

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data interchange format. It uses human-readable text to store and transmit data objects consisting of key-value pairs and arrays. JSON is the de facto standard for:

  • Web APIs and RESTful services
  • Configuration files
  • NoSQL databases (MongoDB, CouchDB)
  • JavaScript/TypeScript applications

When to Convert CSV to JSON

  • API Integration - Most modern APIs expect JSON data
  • Web Applications - JavaScript works natively with JSON
  • NoSQL Databases - Import spreadsheet data into document databases
  • Data Transformation - Use JSON's nested structure for complex data

When to Convert JSON to CSV

  • Spreadsheet Analysis - Open API data in Excel or Google Sheets
  • Legacy Systems - Many older systems only accept CSV
  • Data Sharing - CSV is universally readable
  • Reporting - Generate tabular reports from JSON APIs

Output Format Comparison

Format Best For Example
Array of Objects Most use cases, APIs [{"id": 1}, {"id": 2}]
Object with Keys Quick lookups by ID {"1": {...}, "2": {...}}
Column-based Column operations, charts {"name": [...], "age": [...]}
Records Compact storage [["John", 30], ["Jane", 25]]

Tips for Best Results

  • Consistent data - Ensure all rows have the same number of columns
  • Escape special characters - Quote values containing delimiters or newlines
  • Use headers - First row headers make JSON output more readable
  • Check encoding - Use UTF-8 for international characters
  • Validate JSON - Our tool validates JSON syntax before conversion

Privacy & Security

All conversions happen entirely in your browser. Your data is never uploaded to any server, making this tool safe for sensitive information.