Dedupe rulesRemove duplicate array items: deep mode treats key-order-different objects as equal; dedupe by a field; duplicates keep the first by default.

Array source

Load a JSON array

Deduplicated

Deduplicated output will appear here

Dedupe arrays · keep structure

JSON Deduplicate

Array dedupe · deep / by field / primitive · keep first or last · local

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No upload, no storage

JSON is processed in memory and never sent to a server.

Share via URL fragment

Share links encode data in the # anchor — never sent to a server.

Remember last edit

Optionally keep your last input locally; clear it with one click.

Why use JSON Deduplicate

Deduplicate arrays

Remove duplicate items from a JSON array — primitives, objects and nested structures alike.

Dedupe by field

Decide duplicates by a chosen field (dot paths like user.id), handy for merging records by id.

Deep object dedupe

In deep mode, objects with different key order are recognized as the same, so nothing slips through.

Fast on big arrays

Hash-keyed single-pass dedupe avoids the pairwise-compare performance trap.

Local · no upload

Everything runs in your browser; data is never uploaded or stored.