Unflatten JSON
Convert flat dot-notation keys back to nested objects.
About the JSON Unflattener
The JSON Unflattener rebuilds a nested JSON structure from path-style keys, reversing the flatten operation. It is useful because data coming from CSV files, form submissions, or key-value stores is flat; unflattening restores the hierarchy your application expects.
Like every Pockly tool, it runs entirely in your browser: the JSON you paste is processed on your device and never uploaded to a server.
How to use it
- Paste your JSON into the input panel.
- The result appears automatically in the output panel.
- Fix any reported errors and re-run if needed.
- Copy the result with one click.
Frequently asked questions
Is my JSON uploaded anywhere?
No. Processing happens locally in your browser; your data never leaves your device.
Is there a size limit?
No fixed limit. Documents of several megabytes are processed in seconds.
What if my input is not valid JSON?
The tool shows a clear error message with the location of the problem instead of failing silently.
Are the other JSON utilities related?
Yes — format, minify, sort, validate, flatten, diff, and query all work together; you can chain them by copying output from one into another.