Unflatten JSON
POST
/v1/convert/unflatten-json
curl -X POST "https://convert.toolkitapi.io/v1/convert/unflatten-json" \
-H "X-API-Key: YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{"json": {"user.name": "Alice", "user.address.city": "NYC"}}'# See curl example// See curl example
Response
200 OK
{
"json": {
"user": {
"name": "Alice",
"address": {
"city": "NYC"
}
}
},
"key_count": 2
}How to Use
1
Send a POST request to /v1/convert/unflatten-json with a flat json object and optional separator.
About This Tool
Unflatten a dot-notation key-value object back into a nested JSON structure. The inverse of the flatten endpoint.
Handles dot-separated keys and bracket-notation array indices. For example, {"a.b[0]": 1} becomes {"a": {"b": [1]}}.
Why Use This Tool
- Config Reconstruction — Reconstruct nested configuration from environment-variable-style flat key-value stores.
- Data Restoration — Restore original nested structure from previously flattened data.
Frequently Asked Questions
Are arrays reconstructed?
Yes — bracket indices (key[0], key[1]) are detected and converted back into JSON arrays.
What if keys conflict?
If a key is used as both a value and a prefix (e.g., 'a' and 'a.b'), the nested structure takes priority.
Start using Unflatten JSON now
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