Free tool · 30 seconds
Calculate your sleep efficiency
The share of your time in bed that you actually spend asleep. It is the central measure in cognitive behavioural therapy for insomnia (CBT-I).
Nothing is saved: the calculation happens on your device.
Your sleep efficiency
84%
Time in bed: 8h · Sleep time: 6h 45
Between 75 and 84%. A noticeable part of your time in bed was spent awake. Over several nights, this is the kind of figure CBT-I aims to improve.
One night is not enough: the average is what counts
The ReSomnia sleep diary works out your efficiency every morning, in two minutes, and shows you how it changes over several weeks.
Track my efficiency for freeHow sleep efficiency is calculated
Divide sleep time by time in bed, then multiply by 100.
- Time in bed: from going to bed to getting up, including time awake.
- Sleep time: time in bed, minus the time taken to fall asleep and the time awake during the night.
- Example: in bed from 23:00 to 07:00 (8 hours), 30 minutes to fall asleep and 45 minutes awake: 6h 45 of sleep, an efficiency of 84%.
How to read your result
In CBT-I, an efficiency of 85% or more is often used as a marker of consolidated sleep. The programme adjusts your time in bed according to the average across nights, never according to a single one.
A guide, not a diagnosis
This calculation does not replace a consultation. If your sleep worries you, or if you feel sleepy at the wheel, talk to your doctor.
Frequently asked questions
What is sleep efficiency?
It is the share of your time in bed that you actually spend asleep. To calculate it, divide sleep time by time in bed, then multiply by 100.
What counts as good sleep efficiency?
In cognitive behavioural therapy for insomnia (CBT-I), an efficiency of 85% or more is often used as a marker of consolidated sleep. A single night says little: what matters is the average over one to two weeks.
How can I improve my sleep efficiency?
Spending less time awake in bed is at the heart of CBT-I, along with a regular schedule. These techniques are best done with a professional, especially sleep restriction.
Is the calculation saved?
No. The calculation happens in your browser and nothing is sent. To track your efficiency night after night, the ReSomnia sleep diary works it out for you every morning.
Source
Spielman AJ, Saskin P, Thorpy MJ. Treatment of chronic insomnia by restriction of time in bed. Sleep 1987;10(1):45-56. doi:10.1093/sleep/10.1.45
Your efficiency, every morning.
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