JSON to CSV · Free Online Converter 2026
Convert JSON arrays to CSV format instantly. Upload a JSON file or paste your JSON code, preview the output, and download as CSV. Perfect for data analysis and spreadsheet import.
How it works: Paste JSON array → click Convert → get CSV table. Flattens nested objects into dot notation. Supports arrays of objects.
🎯 Why Convert JSON to CSV?
JSON (JavaScript Object Notation) is the standard format for web APIs and data exchange, but it's not easily readable in spreadsheet applications. CSV (Comma-Separated Values) is universally supported by Excel, Google Sheets, and database tools. Converting JSON to CSV allows you to analyze, filter, and visualize data with familiar spreadsheet tools. Our online converter handles arrays of objects, flattens nested structures using dot notation (e.g., "address.city"), and produces a clean CSV file. The tool is entirely client‑side — your data never leaves your browser — ensuring privacy and security. Whether you're a developer, data analyst, or business user, this tool saves hours of manual work.
The converter supports deep nesting: if your JSON contains objects inside objects, we flatten keys with dot notation (e.g., `user.name`). It also handles arrays of primitive values and objects. The output CSV includes a header row derived from all unique keys across objects. For large datasets, the tool is optimized for speed. You can also upload a .json file or paste the content. After conversion, you can copy the CSV to clipboard or download it directly. 100% free, no registration, no watermarks.
📘 How to Use the JSON to CSV Converter
- Enter JSON data – Paste a valid JSON array (e.g., [{"name":"John","age":30}]) in the left textarea, or upload a .json file.
- Click "Convert to CSV" – The tool processes the JSON and generates a CSV table in the right panel.
- Review output – Check the CSV preview, rows/columns count, and data correctness.
- Copy or download – Use "Copy CSV" to copy to clipboard or "Download CSV" to save as a .csv file.
- Load sample – Click "Load Sample" for a demo JSON array.
✨ Features
⚙️ How the Conversion Works Under the Hood
When you click "Convert", we parse the JSON input using `JSON.parse()`. The input must be an array of objects. We then extract all unique keys from all objects (including nested ones) by recursively traversing the object and building a key map with dot notation. For example, `{a:{b:1}}` yields key `a.b`. Then we create a CSV header using these keys. For each object in the array, we extract values corresponding to the keys (using a helper function that navigates the nested object). Values are escaped (quoted if they contain commas, quotes, or newlines). The result is a standard CSV string. The entire process is done in JavaScript, synchronously, and for large arrays (thousands of objects) it still performs well. Error handling catches invalid JSON or non‑array inputs.
🌟 Use Cases
API data export: Download API responses as CSV for analysis. Database migration: Convert JSON exports to CSV for Excel. Reporting: Prepare data for pivot tables. Data cleaning: Visualize JSON in tabular form.
❓ FAQ
1. What JSON structures are supported?
Arrays of objects. Nested objects are flattened with dot notation. Primitive arrays are not supported as root (must be array of objects).
2. Does it handle large JSON files?
Yes, but browser memory limits apply. For extremely large files (>50MB), performance may degrade.
3. Is my data sent to a server?
No, all processing is local.