Understanding sleep efficiency
Sleep efficiency is the percentage of time in bed that you actually spend asleep (Total Sleep Time divided by Time in Bed × 100). It is a descriptive mathematical metric, not a diagnosis. A percentage alone cannot tell you whether your sleep is healthy or restorative.
If you want to track your patterns over several nights, our Sleep Efficiency Calculator lets you keep a simple, private sleep log on your device to see your multi-night aggregate efficiency.
Where a sleep diary fits in insomnia treatment
The American Academy of Sleep Medicine 2021 guideline on behavioral and psychological treatments for chronic insomnia gives multicomponent Cognitive Behavioral Therapy for Insomnia (CBT-I) a strong recommendation. Our sleep restriction therapy guide explains how that works and when clinical caution matters.
How much sleep do adults generally need?
According to the joint consensus recommendation of the American Academy of Sleep Medicine (AASM) and the Sleep Research Society (SRS), healthy adults should regularly sleep 7 or more hours per night to promote optimal health. The same statement links regularly sleeping less than 7 hours with weight gain, diabetes, high blood pressure, heart disease and stroke, and depression.
Seven hours is a minimum for most adults, not a target that suits everyone: individual sleep needs vary. To see how your recent nights compare with the amount you are aiming for, try the sleep debt calculator.