Merge toolLocal processingArray/object-safe JSON merge

Merge JSON

Merge JSON arrays or JSON objects into one pretty-printed JSON file.

Accepted files

JSON

Add at least two valid files. The first valid file sets the format for this merge batch.

Files to merge

Use Move up and Move down to choose output order.

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Drop files here

Upload multiple JSON files, arrange them, then merge into one download.

No files added yet.

What this tool does

Merge JSON combines multiple JSON files into one pretty-printed result. If every file is an array, the arrays are concatenated into one; if every file is an object, they are gathered into a single array of objects. Invalid JSON is caught up front, so you never get a broken file.

How it works

Add your JSON files, set the order, and the tool parses each one in your browser and combines them by their shape. The merged file downloads as merged.json. Nothing is uploaded.

When to use Merge JSON

Concatenating JSON array exports
Gathering many JSON objects into one array
Catching invalid JSON before it ships
Merging JSON without uploading data