How Oura Measures Sleep
Oura analyzes your sleep by measuring the dynamics of your heart rate, pulse strength, body temperature and movement. Oura’s proprietary algorithms combine these measurements into a detailed picture of your unique sleep patterns.
Because the ring sits firmly on your finger and is in close contact with your skin, it's able to provide accurate pulse and temperature data.
- Photoplethysmogram (PPG): During sleep, Oura measures your Blood Pulse Volume from the arteries on the palm side of the finger with infrared LEDs. The little bumps in the ring band house the infrared LED transmitter and receiver.
- Movement: Oura uses actigraphy to estimate your sleep patterns and sleep-wake cycle.
- Temperature: The occurrence of sleep and wakefulness is closely related to changes in body temperatures. Oura tracks the variations of your body temperature by measuring your skin temperature each night.
Note: The Oura ring automatically detects restful periods, such as naps, during the day, but currently only shows one main sleep period for each day (24 hours). The longest sleep period that has taken place between 6 pm - 6 pm is shown as your sleep in the Oura app and Oura Cloud.