Systems and methods are provided for using earphones with biometric sensors to track a user's biological age over time. In one embodiment, the system includes earphones, including: speakers； a processor； and a heartrate sensor electrically coupled to the processor. In this embodiment, the system also includes a memory coupled to a processor and having instructions stored that, when executed by the processor: receive one or more user determinable biological age parameters including an actual age of the user； determine one or more system measurable biological age parameters based on signals generated by the heartrate sensor； calculate a biological age factor as a function of the user determinable biological age parameters and the system measurable biological age parameters； calculate the user's biological age as a function of the biological age factor and the user's actual age； and display on a display the user's biological age.
