Free online JSON compare and diff tool. Compare two JSON files side by side with visual diff highlighting, three-way merge, AI-powered diff explanation, and JSON Patch export. Supports nested objects, arrays, and smart matching. 100% browser-based.
100% browser-based — your data never leaves your device
JSON Compare is a free online json tool that compare two json files side by side with real-time diff highlighting. It works entirely in your browser — no downloads, no installations, and no server uploads required. backend developers, frontend engineers, DevOps engineers use JSON Compare when they need a fast, privacy-respecting way to process json data without installing additional software. It supports capabilities such as side-by-side diff, syntax validation, deep comparison. Additional features include local processing. Common use cases include reviewing api response changes between deployments, debugging json data differences in configuration files, validating json structure transformations. All processing happens locally using modern browser APIs, which means your data never leaves your device. This makes JSON Compare ideal for working with sensitive data, proprietary code, or any situation where privacy matters.
JSON Compare is a free online json tool that helps you compare two json files side by side with real-time diff highlighting. Key capabilities include side-by-side diff, syntax validation, deep comparison. All processing is done locally in your browser — no data is uploaded, stored, or shared with any server. There are no sign-ups, no file size limits, and no hidden charges. It is commonly used to reviewing api response changes between deployments.
Paste the first JSON document into the left textarea as your baseline.
Paste the second JSON document into the right textarea.
Click Compare to see the diff. Red = removed, green = added, yellow = modified lines.
| Category | Details |
|---|---|
| Input Limits | Maximum file size: Browser memory bound (~2 GB) |
| Nesting depth: Unlimited (browser stack limit) | |
| Supported Formats | JSON, JSONC (with comments), JSON5 (extended syntax) |
| Browser Engine |
|
All operations run entirely in your browser using built-in JSON APIs. No server uploads, no data storage, and no third-party requests.
JSON Compare is ideal when you need to reviewing api response changes between deployments without installing software or uploading data to a server. Since everything runs in your browser, there is no setup time and no risk of your data being stored on external servers. For for persistent editing environments with linting, consider using VS Code with JSON extension. For for server-side JSON processing in scripts, jq (command-line) may be a better fit. JSON Compare fills the gap between heavyweight desktop tools and insecure online services that require uploading your data.
Paste two JSON inputs side by side and click 'Compare'. The tool recursively compares every key, value, and array element.
No. All processing is done locally — your data never reaches any server.
The tool detects added, removed, and modified keys, as well as changes to values, array elements, and nested objects at any depth.
View both JSON inputs side by side with additions, deletions, and changes highlighted in real-time.
Each input is validated independently. Errors are highlighted so you can fix malformed JSON before comparing.
Compares nested objects and arrays recursively to find differences at any depth.
All comparison happens in your browser. Nothing is uploaded to any server.
JSON Compare is useful in a variety of scenarios across different workflows:
Reviewing API response changes between deployments
Debugging JSON data differences in configuration files
Validating JSON structure transformations
For accurate diffs, ensure both JSON inputs have the same structure. Different key orderings won't affect the diff but different nesting levels will show as changes.
Save API responses as JSON files and compare new responses against baselines to catch regressions after deployments.
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Compare two JSON files side by side with real-time diff highlighting.
Paste the first JSON document into the left textarea as your baseline.
Paste the second JSON document into the right textarea.
Click Compare to see the diff. Red = removed, green = added, yellow = modified lines.
Paste or type two JSON documents below to compare them side by side. The tool detects additions, removals, and modifications in nested objects and arrays. Toggle between side-by-side, unified diff, change list, and three-way merge views. Use the schema option to validate both inputs against a JSON Schema before comparing.
{"name":"Alice","age":30,"role":"admin","skills":["js","ts"]}{"name":"Bob","age":25,"role":"editor","location":"NYC"}Format, minify, validate, and explore JSON with tree view, JSONPath queries, and multi-format export — the complete JSON workbench.
JSON CompareCompare two JSON files side by side with real-time diff highlighting.
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