jsonpost
Comparison & Manipulation

JSON Merge Tool

Merge two or more JSON objects with configurable strategies for conflicts and arrays.

Runs entirely in your browser — your data never leaves your device.

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How to use this tool

  1. 1Paste two or more JSON objects.
  2. 2Choose a merge strategy (deep merge, overwrite, or concat arrays).
  3. 3Copy the merged result.

Frequently asked questions

How are conflicts resolved?
You choose the strategy: deep merge combines nested objects, overwrite lets later objects win, and concat joins arrays.
Can I merge more than two objects?
Yes. Add multiple sources and they are merged in order.
Is my data uploaded to a server?
No. Every tool on JSONPost runs entirely in your browser using JavaScript. Your JSON never leaves your device, so it is safe to use with private or sensitive data.

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