Passkey (Face ID / Touch ID)

A sign-in with a passkey (WebAuthn, userVerification: required) applies the negative weight of the webauthn signal: the verification is short-circuited to ALLOW.

1. Create a passkey

2. Sign in with the passkey, then verify

The siteverify response appears here.

What a passkey proves

iCloud Keychain passkeys use the attestation format none: they prove user presence and biometric user verification, not the authenticity of the hardware. For hardware attestation, see the Attestation page. The relying party ID is this page's host name.