Merge JSON
JSONDeep merge two JSON objects: choose deep merge, shallow, or replace-arrays strategy. Shows conflicts.
Combining two config objects sounds simple until arrays and nested keys are involved, and this handles three strategies: deep merge recurses into nested objects with the second object's values winning on conflict, shallow merge only combines top-level keys, and replace-arrays treats array values (like a plugin list) as atomic and swaps them wholesale rather than concatenating or index-merging, since that's rarely what you actually want for config files. Every conflicting key gets surfaced explicitly rather than silently overwritten, which is the main value here over hand-merging with a spread operator. It's built for two objects at a time in the UI. For merging many objects in sequence, the REST API or SDK lets you chain merge calls in a script instead.
How to use Merge JSON
- 1.Paste two JSON objects and pick deep merge to combine them recursively, with the second object's values winning on conflicts.
- 2.Use shallow merge when you only want top-level keys combined, without recursing into nested objects.
- 3.Switch to replace-arrays mode when merging config objects where array values (like a list of plugins) should be replaced wholesale rather than concatenated.
Frequently asked questions
Use via API, SDK, or MCP
cURL# Free: 1,000 req/day · Pro: 10,000 req/day
curl -X POST https://api.utilix.tech/v1/tools/merge-json \
-H "Authorization: Bearer utx_live_..." \
-H "Content-Type: application/json" \
-d '{"base":{"name":"Alice","prefs":{"theme":"dark"}},"override":{"age":30,"prefs":{"lang":"en"}},"strategy":"deep"}'Get an API key from your dashboard · Full API docs →