# HTTP Message Signatures

[2 · Identify](/category/identify/)

| HTTP Message Signatures |
| --- |
| Category | [Identify](/category/identify/) |
| Also known as | RFC 9421 |
| Related | [HTTP Message Signatures](/protocols/http-message-signatures/), [Web Bot Auth HTTP Message Signatures](/protocols/webbotauth/) |

[Identify](/category/identify/) A way to sign chosen components of an HTTP message so a server can verify the sender, defined in RFC 9421. Web Bot Auth uses it to let a crawler or agent prove who it is.

## Instances

Not applicable.

## See also

- [HTTP Message Signatures](/protocols/http-message-signatures/)
- [Web Bot Auth HTTP Message Signatures](/protocols/webbotauth/)

## References

- [https://www.rfc-editor.org/rfc/rfc9421](https://www.rfc-editor.org/rfc/rfc9421) (2026-10-15) VERIFIED

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