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Unflatten JSON
Processed Locally
Convert flat key-value pairs back to nested JSON object structure
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Frequently Asked Questions
JSON unflattening is the reverse of flattening - it converts flat key-value pairs (like "user.name": "John") back to nested objects ({"user": {"name": "John"}}). This is useful when working with databases or APIs that use flat structures.
The tool automatically detects numeric indices in keys (like "items.0", "items.1") and reconstructs them as arrays. Keys without numeric indices become nested objects.
Yes! The tool supports various separators including dot (.), underscore (_), slash (/), and dash (-). Make sure to use the same separator that was used when flattening.
All unflattening happens locally in your browser. Your data never leaves your device and is not sent to any server.