JSON to CSV Converter

Transform JSON data into properly structured CSV format instantly in your browser. Flatten nested objects, select custom columns, preview results, and download — no server needed.

100% Client-Side Instant Conversion No Data Uploaded Nested Flattening

All JSON parsing and CSV generation are performed entirely in your browser. No data is uploaded or stored.

Input JSON Data

Drop a .json file here or click to browse

Or paste JSON directly in the box below

JSON Data *

Supports up to 200,000 characters 0 / 200,000

Conversion Options

Flatten nested objects

Converts {"user":{"name":"John"}} into a flat "user.name" column.

Include header row

First row in CSV will contain column names from JSON keys.

Custom Columns (optional — leave empty for all columns) Use dot notation for nested keys: user.name, user.email. Other columns will be excluded.

Flatten Separator

CSV Output

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How To Convert JSON to CSV

Paste or Upload JSON Data

Drag and drop a .json file, click to browse, or paste your JSON directly into the input area. Supports arrays of objects, single objects, and nested structures.

Enable Flattening If Needed

If your JSON has nested objects like {"address":{"city":"NYC"}}, enable "Flatten nested objects" to convert them into flat columns like "address.city". Choose your preferred separator (dot, underscore, etc.).

Click Convert to CSV

Hit the convert button to start processing. The tool validates your JSON, parses the structure, flattens nested fields if enabled, and generates properly escaped CSV output.

Preview Structured Table

View your data in a formatted table preview with sticky headers, or switch to the raw CSV tab to see the exact output. Optionally filter to specific columns using the custom columns field.

Download or Copy CSV File

Click the green download button to save the .csv file, or copy the CSV data to your clipboard. The file opens in Excel, Google Sheets, LibreOffice, and any spreadsheet application.

Frequently Asked Questions

A JSON to CSV Converter transforms JSON data (typically an array of objects) into Comma-Separated Values format. Each JSON key becomes a CSV column header, and each object becomes a data row. The result is a universally compatible spreadsheet file.

Yes, this tool is completely free with no limits, no watermarks, no sign-ups, and no hidden charges. Convert as much JSON data as you need.

The tool supports: (1) Array of flat objects — most common format like [{"name":"John","age":30}], (2) Single object — {"name":"John","age":30} becomes a one-row CSV, (3) Nested objects — {"user":{"name":"John"}} are flattened to "user.name" columns, (4) Mixed structures with some nested and some flat fields.

When enabled, the converter recursively traverses nested objects and arrays, joining key names with your chosen separator (dot by default). For example, {"address":{"city":"NYC","zip":"10001"}} becomes two columns: "address.city" with value "NYC" and "address.zip" with value "10001". Arrays within objects are converted to indexed keys like "items.0.name".

Enter a comma-separated list of column names in the "Custom Columns" field to export only those specific columns. Use dot notation for nested keys (e.g., "user.name, user.email, age"). If left empty, all columns are included. This is useful when your JSON has many fields but you only need a few.

Arrays inside objects (like {"tags":["a","b","c"]}) are flattened using indexed keys. For example, "tags" becomes "tags.0", "tags.1", "tags.2" as separate columns. If you need a different format, consider pre-processing your JSON or leaving flattening disabled.

Yes. The CSV output follows RFC 4180 standards. Values containing commas, double quotes, or newlines are automatically wrapped in double quotes, and internal quotes are escaped by doubling them. This ensures your CSV opens correctly in Excel, Google Sheets, and other tools.

Absolutely. All parsing and CSV generation happens locally in your browser using JavaScript. No JSON data is sent to any server, nothing is stored, and no one else can access your data. Close the tab and everything is gone from memory.

The tool supports up to 200,000 characters of JSON text when pasting, or files up to 20 MB when uploading. For very large datasets with thousands of rows, the conversion may take a few extra seconds but remains fully client-side.

Yes, the tool is fully responsive and works on smartphones and tablets. You can upload files, paste JSON, configure options, preview the CSV table (which scrolls horizontally within its container), and download the file — all from a mobile browser.

Convert JSON into structured CSV instantly — accurate, fast, and 100% client-side.

JSON to CSV Converter · Convert JSON to CSV Online · Free JSON Parser Tool · JSON to Spreadsheet

JSON to CSV Converter - Free Online Tool for Fast Conversion

JSON to CSV Converter