FreeDev Tools

JSON Merge

Deep-merge two or more JSON objects — later values override earlier ones, arrays concatenate or replace.

Runs locally in your browser. Your input is not uploaded.

How to Use

  1. 1

    Paste JSON documents separated by ---

    Put each JSON object on its own section with a --- line between them.

  2. 2

    Pick the array strategy

    Replace mimics config overrides; Concatenate joins lists.

  3. 3

    Copy the merged result

    The deep-merged, pretty-printed JSON appears instantly.

Frequently Asked Questions

Paste them into the single input separated by a line containing only three dashes (---). Two or more documents are merged left to right.

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