© 2017 There is an unprecedented opportunity for psychologists and behavioral scientists to merge prior theory and research with big data to develop profound insights into the way people use and are affected by music. There are now streaming services that store data from millions of people on their day-to-day musical listening habits; song-level data that tags sonic and emotion attributes for millions of songs; wearable devices (e.g. watches and earbuds) that capture physiological metrics including heartrate and galvanic skin response; mobile technologies that track a person's moment-to-moment activity, location, mood, and sociability; and survey instruments and digital footprints that capture personality and other biopsychosocial metrics in just under a minute. We propose that merging these technologies can create a new age in music psychology that exponentially expands the present knowledge and scope of the field. The new data will advance general areas of music psychology, but will also provide an important opportunity to establish new knowledge about health and well-being that can have a direct impact on the public. By scientifically mapping how music changes behavior and health in the short-term and long-term, Big Music Data can lead to future health initiatives including the development of new evidence-based treatment modalities to be utilized by medical physicians and mental health practitioners. Importantly, industry and streaming services can use these new insights to optimize their technologies and develop music-based health and wellness platforms aimed at improving the well-being of its users, ultimately impacting the way music is used by millions of people globally.