JSON Merger
Combine and merge multiple JSON objects into one seamlessly. Essential free online JSON merger for API integration, data consolidation, and configuration management tasks.
Merge multiple JSON objects into one with configurable deep-merge strategies. Ideal for combining API responses, config files, and dataset consolidation.
JSON Merger
Combine and merge multiple JSON objects into one seamlessly. Essential free online JSON merger for API integration, data consolidation, and configuration management tasks.
About this tool
Merge multiple JSON objects into one with configurable deep-merge strategies. Ideal for combining API responses, config files, and dataset consolidation.
Simply enter your json data to merge it.
Input 1
Input 2
Output appears here...
Simply enter your json data to merge it.
Input 1
Input 2
FAQ
Common questions and answers about this topic.
What does this tool do?
Merges two JSON documents into one, combining fields from both sources.
How are conflicts handled?
When both documents have the same key, the value from the second document takes precedence.
Does it merge nested objects?
Yes, nested objects are merged recursively rather than being replaced entirely.
Is my data sent to any server?
No, JSON merging is handled entirely in your browser. Both documents are merged locally with JavaScript — no data is sent to any server.
How are arrays handled during merge?
You can choose between two array strategies — concat (append the second array to the first) or replace (use the second array entirely). Concat is the default.
How many JSON inputs can I merge at once?
Up to five JSON documents can be merged in a single run. Use the "Add input" button below the second input to add more inputs; they are merged left-to-right.
Can I change which input takes precedence?
Yes. The "Key conflict" dropdown lets you switch between "B overrides A" (default) and "A overrides B" on key conflicts, without re-ordering your inputs.
Can I download or copy the merged result?
Yes. Use the download icon on the output panel to save the merged JSON as a file, or the copy button to put it on your clipboard.