Sleep efficiency calculator

The share of your time in bed that you actually spend asleep. Enter a few nights from memory, or from a diary, and get the number CBT-I programs track.

What sleep efficiency is

Sleep efficiency is total sleep time divided by time in bed, as a percentage. Time in bed runs from when you tried to go to sleep to when you got up. Sleep time is the hours between falling asleep and finally waking, minus the time you were awake in between. Naps during the day do not enter sleep efficiency, so 100% is the most it can be.

It is the number cognitive behavioural therapy for insomnia (CBT-I) is built around, because it measures the thing insomnia breaks: how much of the time you give to sleep is spent sleeping.

Your nights

Fill in at least 3 nights, and add more (up to 7) if you have them. Use the clock times you tried to sleep and finally woke; the rest are minutes. Nothing you type here is saved or sent anywhere.

Night 1
Night 2
Night 3
0 of 3 nights started

This calculator is general education, not medical advice. It cannot diagnose anything or replace a conversation with your doctor. It does not tell you what to change. The research behind sleep efficiency and CBT-I is in What is CBT-I? and the other sleep articles.

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Small Hours is a self-guided program for adults. It is not an emergency service. If you are in crisis, call or text 9-8-8 in Canada or the US at any hour.