Public key inspector
Paste the contents of a .pub file — or a line from
authorized_keys. It is parsed in memory and never written
anywhere.
Never paste a private key
Not here, not into any website. The public half is the file ending in
.pub; the other one — the file with
BEGIN OPENSSH PRIVATE KEY in it — is the secret, and pasting it
anywhere means rotating it. This page refuses to parse one, but the refusal
happens after it has already crossed the network, which is too late.
Everything on this page can be done locally:
ssh-keygen -l -f ~/.ssh/id_ed25519.pub.