JSON Merge – Free Online JSON Object & Array Merger
Free online JSON merge tool to combine multiple JSON objects or arrays securely in your browser.
Tips
- Deep merge combines nested objects
- Right overwrites left on conflicts
- Use preserve left to keep existing values
Table of Contents
Use this free online JSON Merge tool to quickly combine multiple JSON objects or arrays into a single, valid JSON output. Everything runs in your browser, so your data stays private and never leaves your device.
How to use the JSON Merge tool
- Paste or type your first JSON into the left input area.
- Add or paste the second JSON into the right input area.
- Click the merge button to combine them into one JSON result.
- Copy the merged JSON output or download it for use in your app, API, or config.
What this JSON merger is for
- Combining API responses into a single JSON payload.
- Merging configuration files or environment settings.
- Joining JSON arrays from different sources.
- Updating existing JSON objects with new keys and values.
Why use this JSON Merge tool on urwatools
- Instant and free: Merge JSON online in seconds with no registration.
- Privacy-focused: All processing happens in your browser; your JSON is not stored or sent to a server.
- Clean interface: Simple layout focused only on merging JSON, with no distractions.
- Multilingual support: The page can be automatically translated, so you can use the tool in your preferred language.
Work with other JSON tools
After merging your JSON, you may want to format, validate, or convert it. Explore more tools in our JSON tools collection to streamline your workflow:
- Use the JSON Formatter to pretty-print and make your merged JSON easier to read.
- Check correctness with the JSON Validator before using the result in production.
- Compare two structures with JSON Diff to see what changed after merging.
- View and navigate complex data using the JSON Viewer.
Common use cases
- Developers: Merge JSON snippets from documentation, logs, or different services.
- QA & testers: Combine test data sets into a single JSON file.
- Data engineers: Join JSON arrays exported from tools like CSV or Excel converters.
Is this JSON merge secure?
Yes. This tool is designed with privacy in mind. The merge logic runs directly in your browser tab, and your JSON input is not uploaded, logged, or shared.
Frequently asked questions
What does the JSON Merge tool do?
The JSON Merge tool combines two or more JSON inputs into a single JSON output. It is useful for merging objects, arrays, or configuration files without installing any software.
Is my JSON data uploaded or stored?
No. All merging happens in your browser. Your JSON data is not uploaded to a server, not stored, and not shared, which keeps your information private.
Can I merge both JSON objects and arrays?
Yes. You can paste JSON objects or arrays into the inputs. The tool will merge them into a single valid JSON result, as long as the inputs are valid JSON.
How do I check if the merged JSON is valid?
After merging, you can copy the output and open our JSON Validator to confirm that the JSON is syntactically correct before using it in your project.
Do I need an account to use the JSON Merge tool?
No. The JSON Merge tool is completely free to use and does not require any login or registration.
Can I format the merged JSON for readability?
Yes. Once you merge your JSON, you can use the JSON Formatter to pretty-print and indent the result for easier reading.
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