The sample reports my-app, version 1.0.0, a start script and zero dependencies. Sorting keeps those values while formatting the JSON.
BUILD & EXPORT · FREE JAVASCRIPT TOOL
package.json Validator & Viewer
Validate package.json structure, inspect scripts and dependencies, sort keys and export a clean file.
Free to useNo sign-upRuns in your browser
JS
package.json ValidatorLocal browser processing
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A WORKED TASK
Review a package file without installing its dependencies
Paste package.json and inspect the package name, version, script names and dependency count. Use Sort dependencies to arrange supported dependency and script keys alphabetically. This is useful during a review because the tool reads the file without running its scripts or installing packages.
The validator performs basic structural inspection, not the complete npm schema, a dependency vulnerability audit or licence review. Valid JSON and a version string do not establish that a package is safe or installable.
What to check
- Use a JSON object with double-quoted property names; comments and trailing commas are invalid JSON.
- Read lifecycle and start scripts before running any unfamiliar project.
- Review names, version ranges and package provenance separately in the package registry.
TESTED & REVIEWED
Know what this tool does—and where to double-check
- Reviewed by
- HTML Online Viewer project
- Last reviewed
- Processing
- Ordinary processing happens in this browser tab; the tool does not intentionally upload your source.
- Important limitation
- JavaScript checks and transformations cannot prove that application logic is correct. Test the result in its real project before publishing.
PRACTICAL EXAMPLE
Start with a small package.json Validator example
The built-in sample makes the accepted input visible before you use your own project data.Example input
Loaded in the workspace
{"name":"my-app","version":"1.0.0","scripts":{"start":"node index.js"},"dependencies":{}}Run the sample first, then change one value at a time so each result remains easy to explain.
What this example demonstrates
Validate package.json structure, inspect scripts and dependencies, sort keys and export a clean file.
Keep the original file, review the generated result and test production code in its real application before publishing.
COMMON QUESTIONS
package.json Validator FAQ
Is package.json Validator free?
Yes. It is free to use and requires no account.
Does package.json Validator upload my source?
No. Ordinary processing happens locally in the current browser. The JavaScript runner uses a short-lived isolated browser worker.
Can I import and export a file with package.json Validator?
Yes. Import a relevant JavaScript, JSON or text file, then save the input or processed result.