Sleep Efficiency Calculator
Calculate your sleep efficiency percentage and see how it compares to clinical guidelines. Based on the metric used in CBT for Insomnia (CBT-I). Free, instant results.
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Disclaimer: Results are for informational purposes only and do not constitute medical advice, diagnosis, or treatment. Consult a qualified healthcare professional for personal guidance.
What Sleep Efficiency Measures
Sleep efficiency is the cornerstone metric in clinical sleep assessment. It distinguishes between time spent in bed and time actually asleep — an important distinction, as spending excessive time in bed awake reinforces the association between bed and wakefulness, perpetuating insomnia. The formula is simple: (time asleep ÷ time in bed) × 100.
CBT-I: The Gold Standard for Insomnia
Cognitive Behavioural Therapy for Insomnia (CBT-I) is more effective than sleep medication for chronic insomnia, with effects that persist long after treatment ends (unlike medication, which loses efficacy when stopped). Sleep efficiency is used in CBT-I's sleep restriction component: patients initially limit time in bed to their actual sleep time, then extend by 15-minute increments once efficiency exceeds 85%. This approach typically achieves 85%+ efficiency within 4–6 weeks.
FAQs
What is sleep efficiency?
(Time asleep ÷ time in bed) × 100. Above 85% is normal; below 80% indicates poor sleep quality or insomnia.
How to improve sleep efficiency?
Sleep restriction therapy (CBT-I): limit time in bed to actual sleep time, then extend gradually. Consistent wake times and stimulus control (bed for sleep only) also help.
What is a good percentage?
85–90%+ is good. 80–84% is borderline. Below 80% meets clinical criteria for poor sleep efficiency and is a key insomnia marker.