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 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
- What Is a Good Sleep Score? Apple Watch, Garmin and Oura Compared (Sponsored)A good sleep score is about 80 or higher on most devices: 81+ on Apple Watch, 80+ on Garmin, 70+ on Oura (85+ optimal). Bands compared, plus what to check.Sponsored · 5 min read
- How to Fall Asleep When You're Not Tired (Without Forcing It)Don't force it. Wind down in dim light, get up if you're awake after about 20 minutes, and fix the nap, caffeine or wake time that left you wired.4 min read
- How to Stop Oversleeping: A 7-Step Plan That WorksKeep one wake time every day, get enough sleep on weeknights, put the alarm across the room and get light fast. Plus when oversleeping needs a doctor.4 min read
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- 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.