What it does
Useful, focused capabilities
- Strict custom JSON parser
- Line and column diagnostics
- Duplicate-key detection or rejection
- Format, minify, and recursive key sorting
- Safe text-only tree renderer
Developer utilities · browser-local
JSON formatter and validator
Validate, format, minify, sort, inspect, search, copy, and download JSON locally with line and column errors and optional duplicate-key rejection.
Work happens in the current browser. The route does not require an account or a server-side processing job.
Interactive browser workspace
JSON formatter and validator
The live tool is loaded in this browser only. This route does not need camera, microphone, or screen-capture permission for its main task.
Open this local tool →Browser compatibility
Requirements and honest fallbacks
JavaScript and the File API for optional local JSON input and download.
- JavaScript
- File API
- download support
Questions people ask
Clear answers and limits
Does the tool use eval?
No. It uses a strict parser and renders values with DOM text nodes; input is never executed as code or injected as HTML.
Why are comments rejected?
Comments are not part of the JSON standard. Use JSON5 or another format when comments are required.
What happens to duplicate keys?
The validator reports them. Standard object construction keeps the last value unless the reject-duplicates option is enabled.
Does sorting change arrays?
No. Arrays retain order. Sorting applies recursively to object keys only.
Can it validate a JSON Schema?
Not in this route. It validates syntax and structure, not an external schema contract.