Convert JSON to CSV, Free and Private

Convert a JSON array of objects into a CSV spreadsheet, in your browser — opens straight into Excel, Sheets, or Numbers.

Universal File Converter: Private & Fast

Convert images, videos, audio, and documents directly in your browser. Your files never leave your device, ensuring 100% privacy and security.

Data & Docs Converter

Convert CSV to JSON, or Markdown to HTML completely offline.

Mock Data Generator•JSON Formatter

Drop your file here, or browse

Maximum file size: 50 MB

Supported: CSV, JSON, YAML, XML, TXT, B64, MD, DOCX, XLSX, EPUB

Output format

100% In-Browser Processing

Your files are processed strictly in local device memory. Nothing is uploaded — see how, and check for yourself.

How It Works

How to convert files with DuckConvert

Select Your File

Choose the file you want to convert from your device or drag and drop it into the converter.

Choose Output Format

Select your desired output format and any specific settings for your conversion.

Convert & Download

Click "Start Conversion" and wait for the local process to finish, then download your new file.

Don't take our word for it

This conversion runs entirely in your browser — nothing is uploaded. See exactly how, and check for yourself using your browser's DevTools Network tab.

How It Works

Conversion Mechanics

The common case here is an API response or exported record set that arrives as a JSON array — this flattens it into rows and columns so you can open the result in a spreadsheet, filter and sort it, or hand it to someone who doesn't want to touch raw JSON. Nested objects and arrays inside a field are flattened or stringified rather than silently dropped.

Why It's Private

Runs Entirely In Your Browser: Files are decoded and re-encoded strictly in local memory.
No Network Requests: The converter makes no calls to any server — check your browser's DevTools Network tab to confirm.
Nothing to Sign Up For: No account, no upload, and no server-side storage of your files.
Runs On Your Hardware: Processing uses your own device's CPU via Web Workers, not a remote server.

Step-by-Step JSON to CSV Local Guide

Select File

Drop your .json file into the box above.

Configure

Confirm CSV is selected as the output format.

Convert

Click Convert — the array is flattened into rows locally in your browser.

Save Result

Download the resulting .csv file.

Frequently Asked Questions on Secure JSON to CSV Conversion

An array of objects works best — each object becomes one row, and its keys become the column headers.

They're flattened where possible or converted to a string representation, so the data still shows up rather than being lost.

Yes — the output is standard comma-separated CSV that both import without extra configuration.