JSON Unflatten
Reconstruct nested JSON from flat dot-notation keys — the reverse of JSON flattening.
About JSON Unflattening
JSON unflattening is the reverse operation of JSON flattening. It takes a flat object with dot-separated or otherwise delimited keys and reconstructs the original nested JSON structure. For example, {"user.name":"Alice","user.address.city":"NYC"} becomes {"user":{"name":"Alice","address":{"city":"NYC"}}}.
This tool is useful when reading environment variables back into structured configs, processing data exported from flat databases or CSVs, and restoring original JSON structure from flattened storage formats like Redis or environment files.
FAQ
How are numeric keys handled?
Keys that parse as integers in a numeric sequence are automatically converted to arrays. For example, "items.0.id" and "items.1.id" will produce an array at "items" with objects at each index.