pgp.aunsw
pgp.aunsw generates keys, encrypts, decrypts, signs, verifies all locally inside your browser, no private data leaves your device, so you can even run this offline!
This is based on browserPGP which uses the OpenPGP.js library. This fork is in preparation of moving the OpenPGP.js library from v4.10.10 to v5.11.2 (which no longer supports "worker").

PGP encrypt/decrypt diagram