Flatten nested JSON into dot-notation keys, or rebuild nested JSON from flat keys. Runs entirely in your browser.
Flattening turns nested objects and arrays into a single-level object with dot-notation keys, e.g. a.b and a.c.0 — useful for spreadsheets, environment variables, or diffing deeply nested structures. Unflatten reverses this: keys whose next segment is a number become array indices, otherwise an object.
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JSON Flatten / Unflatten flattens nested JSON objects into single-level dot-notation keys or rebuilds nested JSON structures from dot-notation keys.
Nested Input: {"user":{"name":"Alice"}} Flattened Output: {"user.name": "Alice"}
Yes. You can select dots (.), underscores (_), or custom delimiter characters for flattened keys.
Arrays use bracketed or dot-indexed key paths (e.g. items[0].id or items.0.id).
Text & Data
Compare two JSON documents and inspect changed paths locally.
Text & Data
Escape text for embedding in JSON, or unescape a JSON string literal back to raw text.
Text & Data
Beautify, minify, and validate JSON with instant error locations.