package.json Validator
Validate package.json for required fields, semver format, and dependency presence. Catch missing fields and bad semver before installs fail — free, local, no signup.
How to Use the package.json Validator
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Frequently Asked Questions
What fields does it validate?
Required fields (name, version), semver format compliance, valid dependency declarations, script definitions, and common best practices like license and description fields.
Does it check for security issues?
It validates dependency syntax and detects common issues like missing version ranges, duplicate dependencies, and invalid package names. For vulnerability scanning, use npm audit.
Can it validate private packages?
Yes. Private package names (scoped with @scope/name) are validated correctly. The validator ensures the name follows npm naming conventions.
Does it check semver version ranges?
Yes. Version ranges in dependencies (e.g., ^1.2.3, ~1.2.3, >=1.0.0) are validated for correct semver syntax.
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Last updated October 2026