JSON Flatten

Click Convert to flatten or unflatten JSON

Separator:

Preserve Arrays

Max Depth:(0=unlimited)

JSON Sort

JSON to YAML

JSON to XML

JSON to TypeScript

XML Formatter

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Features

Bidirectional processing mode: Supports JSON Flatten and Unflatten, perfect for data structure conversion and format restoration
Flexible array and delimiter control: Customize delimiters (dots, underscores) and choose whether to expand arrays into index keys or keep the original array structure
Deep nesting processing: Efficient recursive algorithm automatically handles complex JSON objects with multiple nesting levels, ensuring complete and logical key-value structure
Multi-scenario data adaptation: Supports MongoDB dot syntax queries, NoSQL database ETL cleaning, Pandas DataFrame dimensionality reduction, and Elasticsearch index mapping workflows
Ultra-fast local processing: Pure browser-local operation without server upload, ensuring privacy and security of sensitive business data, extremely fast processing with no delay

FAQ

How do I flatten a nested JSON object for data analysis?

Simply paste your nested JSON into the input box. The tool automatically converts multi-level keys into single-level key-value pairs connected with dot notation. For example, it converts `{"user": {"name": "Alice"}}` into `{"user.name": "Alice"}`. This dimensionality reduction is perfect for converting complex JSONs into Pandas DataFrames or 2D CSV tables.

How do I restore flattened JSON back to its nested structure?

Our tool includes a powerful Unflatten feature. You can convert flattened key-value pairs with delimiters (like dots or underscores) back into well-structured nested JSON objects with one click, making it easier for developers to debug API data and restore formats.

Can I customize delimiters and handle arrays?

Absolutely. You can choose your preferred delimiter (dots, underscores, etc.) and decide how to handle arrays: expand them into keys with numeric indices (like `items.0`) or keep them as complete values. This adapts to different NoSQL databases and development scenarios.

Can I download and save the flattened or unflattened JSON?

Yes. Once processing is complete, you can copy the processed JSON content with one click or download it directly as a standard .json file. Perfect for developers to save optimized configuration files or interface data.

Does online JSON Flatten/Unflatten compromise my data privacy?

No. Our JSON Flatten processing runs entirely in your local browser, and data is never uploaded to any server. Both sensitive enterprise interface data and personal configuration files enjoy enterprise-grade privacy and security protection.