Sleep Efficiency Calculator

The share of your time in bed that you are actually asleep. Below 85% is the threshold clinicians treat as poor, and it separates not enough hours from the hours not working.

Eight hours in bed is not eight hours of sleep, and the gap between the two is the number that actually matters.

Sleep efficiency is the share of time in bed that you spend asleep. It is the single most useful figure for telling apart two very different problems: not spending enough time in bed, and spending plenty of time there while something keeps interrupting you.

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