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security.txt Validator

Lint Contact, Expires, duplicate fields, unknown fields, and URI shape locally.

security.txt validator workspace

Lint security.txt fields and copy a normalized RFC 9116 file.

security.txt validation action

Paste a security.txt file and check required fields, dates, duplicate fields, unknown fields, and URI shape.

security.txt input

Cleaned file

Validation

1 contacts5 fields0 errors0 warnings

Ready

Contact and Expires are present, the date is in the future, and the cleaned file is ready to copy.

Validation runs locally in this browser tab. Utilumo does not fetch your site or upload the file.

Questions

What does Security.txt Validator check?

It checks pasted security.txt content for required fields, duplicate single-use fields, URI shape, expiration, and unknown names.

Does this fetch my live security.txt URL?

No. Paste the file content. The validator runs locally and does not make external requests.

Which fields are required?

RFC 9116 requires Contact and Expires. The validator also checks duplicate single-use fields and unknown field names.

Can warnings still be published?

Maybe. Warnings highlight issues worth reviewing, while errors cover missing or invalid core fields.

Does Utilumo upload my input?

No. This tool is designed for local browser processing and does not send your input to a server.

Do I need an account?

No. Utilumo tools are built to work without accounts or sign-in.