JSON Merge Tool is a small, free utility for combining two JSON files into one. It started as a simple need: merging configuration files, API responses, or data exports without writing a script every time.
Paste two JSON objects into the input boxes and click Merge. The tool combines them recursively — if both files contain a nested object at the same key, their contents are merged together rather than one overwriting the other entirely. Where a plain value or array appears in both files, the second file's value is used.
Developers, students, and anyone working with config files, API payloads, or structured data who needs a quick merge without installing anything or writing code.
This first version supports exactly two files and does not merge arrays element-by-element. Support for more files and smarter array handling is planned.
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