CSV to JSON

About this tool

CSV to JSON is a free daily-quota online CSV to JSON converter — no installation, no sign-up, ready to use. Just upload a .csv file and it converts to well-structured JSON in one click, supporting both object-array and 2D-array output, auto-adapting to multiple delimiters, and smartly recognizing numbers, booleans, null, and other types, with optional pretty-printed output. It supports batch conversion and all platforms, and all processing happens entirely in your browser, with 100% privacy — your files are never uploaded to any server. Whether you are doing API development, data analysis, or data migration, it handles everything with ease — results rival professional developer tools. (Note: "free quota" refers to the daily free usage count, not unlimited use; for high-frequency or professional needs, you can unlock more by becoming a member)

How to Use

1. Add Files

   Click the upload area or drag and drop a CSV file into the upload box. .csv format is supported and you can add multiple files at once.

2. Configure Options

   In the parameter panel, choose the output structure (object array or 2D array), CSV delimiter, and whether to pretty-print.

3. Start Processing

   Click the "Start Processing" button — the tool parses the CSV and generates the corresponding JSON data.

4. Download

   Click "Download" after conversion to get the JSON file; multiple files support packaged download as a ZIP.

Use Cases

• API development: quickly turn CSV data into JSON for interface debugging and Mocking
• Data analysis: convert exported CSV data into JSON for easy processing in scripts or frontend projects
• Data migration: batch-convert CSV files into JSON for database imports or program consumption
• Data display: turn tabular data into structured JSON for visualization pages or mini-programs

Key Advantages

1. Daily Free Quota

   Get free usage count every day, so light everyday conversions cost nothing and you can experience the full features without paying.

2. Privacy & Security

   All conversions are done entirely in your browser — files are never uploaded to any server and your data stays on your device.

3. Smart Type Recognition

   Automatically converts numbers, booleans, and null into the corresponding JSON types, so your data works out of the box.

4. Flexible Output

   Supports both object-array and 2D-array output structures — choose as needed for different scenarios.

5. Easy to Use

   No installation, no sign-up, and ready to use — upload and convert with no learning curve.

Output Structure Reference

The tool supports two output structures. Choosing the right one helps your data get consumed better by programs — here is a quick comparison.

Output Structure	Data Form	Best For
Object array (header as key)	[{ "name":"John", "age":25 }]	API debugging, program consumption
2D array (raw rows)	[["name","age"],["John",25]]	Preserving raw structure, batch processing
Pretty print	Formatted indented JSON text	Reading, debugging, code demos

FAQ