MyAITools
Merger

JSON Merge

JSON Merge is a free online merger that helps you deep-merge two JSON documents; choose how to handle conflicting keys and arrays. JSON Merge uses 3 input fields, returns 1 output value, and runs in your browser on the device.

Key facts

Inputs
3 fields: JSON A (base / left), JSON B (overlay / right), and Strategy
Outputs
1 value: Merged
Runtime
your browser on the device
Mode
Merger
Privacy
Files and text stay in the browser session.
Cost
$0, no account required

How to use JSON Merge

  1. 1

    Paste or fill in the input

    Enter your text or values into the input fields on the page.

  2. 2

    Run the utility

    Click Compute to run the utility in your browser and review the result.

  3. 3

    Copy the output

    Copy the output value you need from the result panel.

JSON Merge details

First, enter JSON A (base / left) in JSON Merge. Next, review Merged. Additionally, JSON Merge uses 3 input fields and 1 output block so the result is easy to scan and copy.

Combine two JSON objects with a deep recursive merge. Choose whether the right or left side wins on conflicting scalars, and whether arrays at the same path should be concatenated or replaced. Useful for layering config files, applying overrides on top of defaults, or building composite payloads. Runs entirely in your browser; free, online, no upload.

Common searches

  • json merge
  • deep merge json
  • json combine
  • merge two json
  • json overlay
  • json config merge

Related tools

Tools that work with the same formats — most users open one of these next.

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Generate C# classes from JSON with typed properties for nested objects and arrays.

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Frequently asked

What is JSON Merge?

JSON Merge is a free online merger that helps you deep-merge two JSON documents; choose how to handle conflicting keys and arrays. JSON Merge uses 3 input fields, returns 1 output value, and runs in your browser on the device.

What inputs and outputs does JSON Merge use?

JSON Merge uses 3 input fields: JSON A (base / left), JSON B (overlay / right), and Strategy. JSON Merge returns 1 output value: Merged.

Do my files and data stay private?

Yes. JSON Merge runs entirely in your browser using your device's CPU. Files and text are never uploaded to our servers, so your data stays private.

How do I use JSON Merge?

Open JSON Merge, paste or fill in the input fields, and the result updates instantly. JSON Merge runs in your browser with no upload and no waiting.

Which browsers does JSON Merge support?

Any modern browser works in Chrome, Firefox, Safari, and Edge on desktop and mobile. JSON Merge uses standard web APIs and does not require any plugin, extension, or sign-up.