Deep merge two JSON objects with conflict resolution. JSON Merger is a free online tool from the ToolsRift JSON Tools collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.
Paste two JSON objects and the merger deep-combines them, letting the second override the first where keys collide.
Nested objects are merged recursively rather than replaced, so only the specific keys that overlap are combined or overridden.
By default the second object overrides the first for conflicting keys, ideal for applying overrides on top of defaults.
Arrays are typically replaced rather than concatenated, since merging list items by position is often ambiguous.