Security
npm Package Name Validator
Enter an npm package name (scoped or unscoped) and validate it against npm publish rules. Checks casing, character set, scope format, and reserved name conflicts. All validation runs in your browser.
No data is transmitted — everything runs locallyTool
About this tool
npm Package Name Validator
The npm Package Name Validator checks package names against npm's naming rules — lowercase, URL-safe characters, valid scope format — and returns specific rule violations.
• Validate a new package name before running npm publish to avoid a rejected publish
• Check whether a scoped package name (@scope/name) is correctly formatted
• Debug a 'package name can only contain URL-friendly characters' publish error
• Verify a package name is safe before registering a dependency in your package.json
Next step
Alerting Threshold Calculator — Compute multi-window SLO burn rate alert thresholds from the Google SRE Workbook method.
Open Alerting Threshold Calculator →
FAQ
What does this tool tell you?
The npm Package Name Validator checks package names against npm's naming rules — lowercase, URL-safe characters, valid scope format — and returns specific rule violations.
What affects the result most?
npm package names must be lowercase — uppercase triggers publish failure. Allowed characters: [a-z 0-9 - _ .] plus @ for scoped packages (@scope/name). Name must not start with a period or underscore.
How should I use the result?
Treat the tool's output as a first-pass check, not a proof of correctness. A clean pass means no issues in the patterns this tool recognizes; a failure points to a specific problem you can investigate in your source. The underlying spec is the authoritative source for edge cases.
Related tools