This white paper discusses passkey security, focusing on the transition from traditional password-based authentication to modern methods that resist phishing attacks. It outlines the security properties of passkeys, which leverage asymmetric cryptography to eliminate shared secrets and store private keys securely on user devices. The document details the advantages of device-bound passkeys, which offer stronger protection compared to synced passkeys, while also addressing potential risks associated with cloud storage. The paper emphasizes the importance of user verification and platform security in mitigating threats from client-side malware and session hijacking. It also highlights endorsements from government bodies such as CISA and NIST, which recognize FIDO-based authentication as a robust standard for multi-factor authentication. Additionally, the document analyzes various attack classes and how passkeys provide resilience against scalable attacks, making them a compelling choice for organizations aiming to enhance their authentication strategies.