Definition
A passkey is a cryptographic credential that replaces traditional passwords for account authentication. Based on the FIDO2/WebAuthn standard, passkeys use public-key cryptography tied to a device's biometric authentication (Face ID, Touch ID) or PIN. When logging in, the device generates a cryptographic signature that proves identity without transmitting a password. Passkeys are phishing-resistant and eliminate the risk of password breaches. Major platforms including Google, Apple, and Microsoft have adopted passkeys as the next generation of account security.