Sleep calculator / Sleep efficiency
Sleep Efficiency Calculator
Find out what share of your time in bed you actually spend asleep. It's one of the simplest ways to measure sleep quality.
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- No sign-up
- No app
What is sleep efficiency?
Sleep efficiency is the time you spend asleep divided by the time you spend in bed. If you're in bed for 8 hours and asleep for 7, your efficiency is 87.5%. Sleep doctors use it because it's simple and it tracks with how rested people feel.
What's a good score?
- 85% or higher: good. This is the usual benchmark for healthy sleep.
- 75–84%: fair. You're spending a noticeable chunk of the night awake.
- Below 75%: low. Common with insomnia, stress, or a sleep schedule that doesn't fit your body.
How to raise your sleep efficiency
- Go to bed only when you're sleepy, not just because it's time.
- Get out of bed if you can't sleep after about 20 minutes. Do something calm in dim light and come back when drowsy.
- Keep the same wake-up time every day, even after a bad night.
- Use the bed for sleep (and sex) only, not scrolling or work.
- Cut late caffeine. Find your caffeine cutoff.
These are core parts of cognitive behavioral therapy for insomnia (CBT-I), the first-choice treatment for long-term insomnia. If your efficiency has been low for weeks, a doctor can help.
Frequently asked questions
What is a normal sleep efficiency?
85% or higher is generally considered normal for healthy adults. Some healthy older adults run a little lower.
Can sleep efficiency be too high?
Very high efficiency (close to 100%) combined with falling asleep instantly can be a sign you are short on sleep. A few minutes to fall asleep and brief wake-ups are normal.
Do sleep trackers measure efficiency?
Many do, but consumer trackers estimate sleep from movement and heart rate, so they can be off, especially at spotting time awake. Your own estimate is a useful cross-check.
Related reading
- Is It Bad to Lie in Bed Awake? The 20-Minute Rule ExplainedLying awake for a long time can train your brain to link bed with being awake. How the 20-minute rule works and what to do when you get up.3 min read
- Time in Bed vs Time Asleep: Why 8 Hours in Bed Isn't 8 Hours of SleepTime in bed includes falling asleep and waking in the night, so it's always more than your sleep. How to work out the gap and what's normal.4 min read
- What Is Sleep Restriction Therapy? How It Works in CBT-ISleep restriction therapy treats insomnia by matching time in bed to the sleep you actually get. How it works and why to do it with a clinician.4 min read
More free sleep tools
All completely free, no sign-up.
- Sleep CalculatorBest bedtime or wake-up time, based on 90-minute sleep cycles.
- Nap CalculatorWhen to set your alarm for a power nap or a full-cycle nap.
- Sleep Debt CalculatorHow much sleep you owe this week, and how to pay it back.
- Caffeine Cutoff CalculatorHow much caffeine is still in you at bedtime, and your latest cup.
- Sleep Needs by AgeRecommended hours for every age, from newborns to over-65s.
- Shift Work Sleep CalculatorWhen to sleep and stop caffeine around any shift, including nights.
- Jet Lag CalculatorDays to adjust, plus a shift-before-you-fly schedule.
These results are general estimates, not medical advice. Everyone's sleep is a little different. If you're often exhausted despite enough time in bed, snore loudly, or have been told you stop breathing in your sleep, see a doctor.