JSON Flattener
Flatten nested JSON into dot-notation keys or unflatten back. E.g. {"a":{"b":1}} → {"a.b":1}.
#json#flatten#unflatten#nested#dot notation#developer
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How to use
- 1Paste your JSON (nested objects and arrays are supported)
- 2Choose mode: Flatten or Unflatten
- 3Optional: change the separator character (default is ".")
- 4Click "Process" and copy the result
Frequently Asked Questions — JSON Flattener
Can I use a custom separator?+
Yes. The default is dot (.), but you can use "/" or "__" or any string as separator.
How are arrays handled?+
Arrays are flattened using numeric indices: e.g. {arr: ["a","b"]} → {"arr.0":"a","arr.1":"b"}.
Can I unflatten back to the original structure?+
Yes. Switch to Unflatten mode and paste a flat dot-notation JSON to restore the nested structure.