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Free Security.txt Checker

Fetch and parse a public security.txt file so security teams and site owners can confirm vulnerability disclosure contacts, expiry dates, canonical URLs, policy links, and related RFC 9116 fields.

Common use cases

Frequently asked questions

Where should security.txt live?

The standard location is /.well-known/security.txt. NerdTools also checks /security.txt as a fallback.

What fields are important?

At minimum, RFC 9116 expects Contact and Expires fields. Canonical, Encryption, Policy, Acknowledgments, and Preferred-Languages can provide useful extra context.

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