Add the base object
Paste the default or earlier JSON configuration.
JSON object merger
JSON Merge Tool
Combine a base JSON object with an override object. Nested objects are merged recursively while updated scalar and array values come from the second document.
No upload Free to use Works on mobile
Data tool
JSON Merge
Options
Merged JSON
0 resultsHow to use JSON Merge
Add overrides
Paste the properties that should be added or replace existing values.
Review the merged object
Nested objects are combined and the final result is formatted for inspection.
Common uses
Environment configuration
Apply production overrides to shared defaults.
API object assembly
Combine partial objects before a request.
Fixture preparation
Build test records from reusable base data.
JSON Merge FAQ
Is JSON Merge free to use? +
Yes. JSON Merge is free to use without an account or usage meter.
Is my data uploaded or stored? +
No. The processing for this tool runs locally in your browser. Entered content is not sent to our server.
How are arrays merged? +
Arrays from the second JSON document replace arrays at the same path. This avoids guessing whether array values should be appended, deduplicated, or reordered.
Keep working
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