Embodiments of the present invention provide a system for generating a real-time audio token for multi-factor audio authentication. The system is configured for determining that a user is accessing an entity resource, via a user device of the user, causing a cryptographic device associated with the user to generate and emit a dynamically varying continuous audio tone, performing authentication of the user based at least in part on the dynamically varying continuous audio tone, determining that the authentication based at least in part on the dynamically varying continuous audio tone is successful, and allowing the user to access the entity resource based on determining that the authentication based at least in part on the dynamically varying continuous audio tone is successful.