JSON Flattener
Flatten nested JSON into dot-notation keys.
Nested JSON, flattened
Deeply nested JSON is awkward for spreadsheets and diffs. This flattens it into single-level keys using dot notation, so a value nested under a then b collapses to the single flat key "a.b" — easy to scan or load into a table.
Flattened keys load neatly into a spreadsheet column or a CSV, and they make diffs readable, since a change shows as one altered line instead of a reshuffled nested block.
Reversible
Use the unflattener to rebuild the nested shape. Flattening runs in your browser and nothing is uploaded. Your data is flattened on your device and never uploaded.
Frequently asked questions
What does this json flattener do?
Flatten nested JSON into dot paths that are easier to scan and export.
How are arrays flattened?
Array positions become part of the key, so {"tags": ["a", "b"]} becomes "tags.0": "a" and "tags.1": "b".
What happens to empty objects and arrays?
They disappear, because there is no value underneath to write. If an empty field must survive, add a placeholder value before flattening.
Can I reverse the flattening?
Yes, with the JSON unflattener, which rebuilds nested objects from dot keys and turns numeric parts back into arrays.
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