Sleep music refers to any music or sound designed to promote relaxation and support the transition into sleep. It has been used across cultures for thousands of years — from lullabies sung to infants to classical compositions specifically written to induce calm — and remains a popular and effective tool for improving sleep. The way music influences sleep is closely linked to its effect on the autonomic nervous system. Slow, gentle music with a tempo of around 60 beats per minute tends to synchronize with the body’s natural resting rhythms, slowing the heart rate, reducing blood pressure, and decreasing levels of the stress hormone cortisol. This physiological relaxation response makes it easier to fall asleep and may improve sleep quality. Sleep music encompasses a wide range of styles, including classical music, ambient music, nature sounds (such as rainfall, ocean waves, or birdsong), binaural beats, and specially composed sleep tracks. White noise and pink noise are also commonly used as auditory aids for sleep, as they mask disruptive environmental sounds. Research suggests that listening to calming music for 45 minutes to an hour before bed can significantly reduce the time it takes to fall asleep, decrease nighttime awakenings, and improve overall sleep quality. These benefits have been found in both adults and children. Sleep music is available through streaming services, sleep apps, and dedicated sleep sound devices. It can be particularly helpful for people who live in noisy environments or who find it difficult to quiet their minds at bedtime. Using a sleep timer to ensure the music fades out after you fall asleep can prevent disturbance later in the night.