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JSON CSV Converter

Bidirectional conversion between JSON and CSV formats with nested object flattening and custom delimiters

About JSON-CSV Converter

JSON (JavaScript Object Notation) and CSV (Comma-Separated Values) are two commonly used formats for data exchange and storage.

This converter allows you to easily convert between JSON and CSV formats. It can handle nested objects, arrays, and various data types, making data conversion quick and simple.

Key Features

Bidirectional conversion: JSON to CSV and CSV to JSON
Nested object flattening option support
Custom delimiter support (comma, semicolon, tab, pipe)
Optional header row inclusion
Direct download of converted files
100% client-side processing, data secure

Supported JSON Formats

Object arrays: [{...}, {...}]
Single object: {...} (converted to single row)
Nested objects (flattened using dot notation)
Arrays as values (converted to JSON string)

Common Use Cases

Export API response data to spreadsheets
Import CSV data into web applications
Data migration between systems
Generate reports from JSON data

Best Practices

Appropriately Flatten Nested Objects

Enable "Flatten Nested Objects" to convert nested JSON into flat CSV columns using dot notation (e.g., 'address.city'). For simple structures, disable this option to keep output cleaner.

Validate JSON Before Conversion

First use a JSON validator to ensure your JSON format is correct. Invalid JSON will cause difficult-to-diagnose conversion errors.

Handle Arrays in Values

Arrays as values will become JSON strings in CSV. If you need each array item on a row, preprocess JSON to flatten arrays first.

Use Appropriate Delimiter

If your data contains commas, use semicolon or tab delimiter. In European regions where commas are used as decimal separators, semicolons are preferred.

Troubleshooting

Why are some columns missing?

CSV uses the keys of the first object as headers. If subsequent objects have additional keys, these columns won't appear. Ensure all objects have consistent keys.

Why does [object Object] appear in CSV?

Unflattened nested objects become string representations. Enable "Flatten Nested Objects" or preprocess JSON to remove nesting.

Why does CSV to JSON produce empty array?

Check if your CSV has content and if the correct delimiter is selected. Empty lines or delimiter mismatches can cause silent parsing failures.

How to handle CSV with different data types?

CSV to JSON treats all values as strings by default. For numbers, booleans, or null values, you may need to post-process the JSON output.

Frequently Asked Questions

Is my data secure?

Yes, absolutely secure. The conversion process runs entirely in your browser using JavaScript. Your JSON and CSV data are never sent to our servers.

Can I convert nested JSON objects?

Yes. Enable the "Flatten Nested Objects" option to convert nested structures into flat CSV columns (e.g., 'user.address.city').

How to open CSV in Excel?

Simply click "Download" to get the .csv file, which can be opened directly in Microsoft Excel, Google Sheets, or Apple Numbers.

Can CSV be converted back to JSON?

Yes! Just switch to "CSV → JSON" mode, paste your CSV data, and click the convert button.

What delimiters are supported?

Comma (,), semicolon (;), tab, and pipe (

Is there a file size limit?

Since it runs in the browser, the limit depends on your computer's memory. Usually can easily handle files of several megabytes.

Data is processed locally in your browser by default and will not be uploaded to any server. Upload will be clearly indicated if required.

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