Convert JSON arrays to CSV and CSV back to JSON online for free. Handles nested values, quoted fields, and commas in values — instant bidirectional conversion.
JSON to CSV Converter is a free online tool that converts JSON arrays into CSV (Comma-Separated Values) format and vice versa. It uses the first object's keys as CSV column headers and properly handles values containing commas, double quotes, and newlines by following the RFC 4180 CSV standard. The reverse direction parses CSV with a state-machine parser that correctly handles quoted fields. All processing happens entirely in your browser — no data leaves your device.
Use this tool when you need to quickly transform data between JSON and CSV formats — for example, converting an API response into a spreadsheet-friendly format, or preparing CSV data for import into a system that expects JSON. It is particularly useful for data analysts, developers working with REST APIs, and anyone who needs to move data between web applications and spreadsheet tools like Excel or Google Sheets.
Developers convert JSON API responses to CSV for analysis in spreadsheet applications. Data analysts transform CSV exports into JSON for consumption by web applications and dashboards. QA engineers convert test data between formats for different testing tools. Database administrators export query results as JSON and convert to CSV for reporting. Product managers convert user feedback data between formats for different analysis tools.
Essential terms and definitions related to JSON to CSV Converter.
A plain text file format that stores tabular data with each row on a new line and values separated by commas. CSV is the universal interchange format for spreadsheets, databases, and data tools. Despite its simplicity, CSV has no built-in type system — all values are strings, and type inference must be handled by the consuming application.
The formal specification for the CSV format defining rules like: fields containing commas, double quotes, or newlines must be enclosed in double quotes; double quotes within fields are escaped by doubling them (""); and CRLF ( ) is the standard line ending. Adherence to RFC 4180 ensures compatibility across different CSV parsers and spreadsheet applications.
The process of converting structured data (objects, arrays) into a format that can be stored or transmitted and later reconstructed. JSON and CSV are two common serialization formats: JSON preserves data types and nesting, while CSV is flat and typeless. Converting between them involves flattening (JSON→CSV) or type inference (CSV→JSON).
The tool expects a JSON array of objects where each object has the same keys. The first object defines the CSV column headers. Nested objects are not flattened — they are serialized as JSON strings within the CSV cell.
Values that contain commas, double quotes, or newlines are automatically wrapped in double quotes in the CSV output. Double quotes within values are escaped by doubling them, following the RFC 4180 CSV standard.
Yes. The generated CSV uses standard formatting compatible with Excel, Google Sheets, and other spreadsheet applications. Simply save the output as a .csv file and open it in your preferred spreadsheet program.
The CSV to JSON conversion treats all values as strings by default, since CSV has no type system. If you need typed values, you will need to post-process the JSON output to convert string numbers and booleans to their native types.
Common errors developers encounter and how to resolve them.
TypeError: data.map is not a function — JSON array expected JSON to CSV conversion only accepts JSON array (list) format. If your input is a single JSON object ({...}), wrap it in an array: [{...}]. In API responses, data is typically returned as an array under a key like data, results, or items; extract that key's value (response.data) and paste it into the tool.
Non-ASCII characters display incorrectly in CSV output (encoding issue) CSV files use UTF-8 encoding by default, but Excel may assume a different encoding (like Windows-1252) based on the system locale when opening the file. Solution: when opening the CSV file in Excel, use "Data → From Text/CSV" and select UTF-8 as the encoding. Alternatively, a UTF-8 BOM (Byte Order Mark) can be added to the beginning of the file.
Nested object values show as [object Object] in CSV CSV is a flat data format and does not natively support nested JSON structures. This tool serializes nested objects as JSON strings, but some tools may display them as [object Object]. As a solution, flatten the nested objects in your JSON data before conversion (e.g., address.city format) or use a JSON structure containing only flat key-value pairs.