Rebuild nested JSON
Paste a flat object whose keys are dotted paths and rebuild the original nested JSON. Turn on array rebuilding so numeric path segments become arrays, the exact inverse of Flatten JSON. The result is saved privately in your account.
No sign-up needed, runs instantly in your browser.
How it works
- 1Paste your flat JSON object
- 2Set the separator and options, then press Run
- 3Download the nested JSON or find it in your files
Frequently asked questions
- When do I get arrays vs objects?
- With "Rebuild arrays" on, integer path segments (0, 1, 2…) create arrays; off, every level stays an object with string keys.
- Does it reverse Flatten JSON exactly?
- Yes, use the same separator and keep array rebuilding on to reproduce the original structure.
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