Stamper will timestamp a content sent via HTTPS as follows. The content must be submitted using the POST method to https://timestamp.stampertest.itconsult.co.uk/stamp-pgp, for example to timestamp a local file "examplefile.txt":-
$ curl -H "Content-Type: text/plain" --data-binary '@examplefile.txt' https://timestamp.stamper.itconsult.co.uk/stamp-pgp -----BEGIN PGP SIGNATURE----- Comment: Stamper id: 2114407 iHUEABYKAB0WIQT/IHN7o3gaHZ+7jLHo6IPRD28swgUCaUbfyQAKCRDo6IPRD28s wuYjAQC/rhEnzWNh63Y4IdCL/kQEcvcwCaiEyFQnm1YvndCPQAEAke8rgeaWPCwF B8ku9GFCeZFoySa1tfhAL6NZMtzr4Ac= =cksR -----END PGP SIGNATURE-----which then returns the timestamp. Alternatively, the timestamp output can be written directly to a file:-
$ curl -H "Content-Type: text/plain" --data-binary '@examplefile.txt' -o examplefile01.asc https://timestamp.stamper.itconsult.co.uk/stamp-pgp
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 326 0 258 100 68 230 60 0:00:01 0:00:01 --:--:-- 291
$ cat examplefile01.asc
-----BEGIN PGP SIGNATURE-----
Comment: Stamper id: 2114408
iHUEABYKAB0WIQT/IHN7o3gaHZ+7jLHo6IPRD28swgUCaUbgDgAKCRDo6IPRD28s
wnUpAP9Ljfav/Sjkk/2XChNgE0jFUlZJdk+4AM6zuwRue+q3pQEAzP4c454JNAah
4nbgN9jqbbTS8JGbCLJS6OKR6YsCfQw=
=nvyq
-----END PGP SIGNATURE-----
This can be validated:-
$ gpg --verify examplefile01.asc examplefile.txt gpg: Signature made Sat 20 Dec 2025 17:42:38 UTC gpg: using EDDSA key FF20737BA3781A1D9FBB8CB1E8E883D10F6F2CC2 gpg: Good signature from "stamper.itconsult.co.uk - Timestamping Key" [full]