JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate. It supports objects, arrays, strings, numbers, booleans, and null, and is widely used for API data transmission.
CSV (Comma-Separated Values) is a simple tabular file format where each line represents a record and fields are separated by a delimiter. CSV files can be opened directly by spreadsheet software like Excel and Google Sheets, making them ideal for data storage and display.
• Structure: CSV is flat tabular; JSON supports nested objects and arrays
• Size: CSV files are smaller; JSON includes key names so it's larger
• Usage: CSV for data export and spreadsheets; JSON for APIs and programmatic processing
• Types: CSV values are all strings; JSON preserves original data types
This JSON to CSV tool supports bidirectional conversion with a simple interface:
JSON to CSV: Paste a JSON array (e.g., [{"name":"John","age":25}]) into the input box, select a delimiter, and click "JSON → CSV". The tool automatically extracts all keys as CSV headers and converts each record to a row. Nested objects are flattened and nested arrays are converted to JSON strings.
CSV to JSON: Paste CSV text into the input box, ensure the first row is the header (or uncheck "First row is header"), select the correct delimiter, and click "CSV → JSON". The tool parses each row into a JSON object with keys from the header row.
Custom Delimiter: The default delimiter is comma. You can also choose semicolon, tab, pipe, or any custom character. This is useful when handling European-style CSVs (commonly semicolon-delimited) or TSV files.
Preview & Download: After conversion, click "Toggle Preview" to view data in table format, or click "Download File" to save the result as a .csv or .json file.
API Data Export: Convert JSON data returned by REST APIs to CSV format for easy analysis in Excel. For example, convert a user list API response to CSV for data reporting.
Database Migration: CSV is a universal intermediate format when migrating data between systems. Convert JSON data to CSV for database import, or convert database-exported CSV to JSON for programmatic use.
Data Cleaning & Transformation: Data analysts frequently need to convert between JSON and CSV formats. This tool handles format conversion quickly without writing scripts.
CSV Standard (RFC 4180): The CSV standard specification defines field quoting rules — fields containing delimiters, newlines, or double quotes must be wrapped in double quotes, and internal double quotes must be escaped as two consecutive double quotes. This tool strictly follows this standard.
Nested JSON Handling: When JSON objects contain nested structures, this tool uses a flattening strategy: {"user":{"name":"John"}} is converted to a user.name column. Nested arrays are serialized as JSON strings.
Character Encoding: This tool uses UTF-8 encoding for all text, with full support for Chinese, Japanese, Korean, Emoji, and other Unicode characters. Downloaded CSV files also use UTF-8 encoding (with BOM) for correct Excel recognition.
Absolutely not. All conversion operations are performed locally in your browser using pure frontend JavaScript. No network requests send your data to any server. You can verify this by opening the browser developer tools (F12) and checking the Network panel.
Yes. For nested objects, the tool flattens nested properties using dot notation (e.g., user.name). Nested arrays are converted to JSON string output. For simple flat JSON arrays, all keys are extracted directly as CSV column headers.
It supports comma (,), semicolon (;), tab, pipe (|), and custom delimiters. You can choose the appropriate delimiter for your needs, and the tool correctly handles fields containing the delimiter (wrapped in double quotes).
Yes. The tool strictly follows the RFC 4180 standard. Fields containing delimiters, newlines, or double quotes are automatically wrapped in double quotes, and internal double quotes are escaped as two consecutive double quotes.