Sleep debt calculator
How much sleep do you owe yourself?
Put in the hours you slept each night and the hours you do well on. You get the week's shortfall, the nights that built it, and the arithmetic of paying it back.
Your last seven nights
Hours actually asleep, not hours in bed.
Nothing you enter is saved or sent.
What sleep debt means
Sleep debt is the running gap between the sleep you need and the sleep you got. Need eight hours and sleep six and a half, and you are ninety minutes down. Do that five nights in a row and the week is seven and a half hours short, close to a whole night.
The calculator adds up each night's shortfall. A long night counts against the debt, which is why a good weekend pulls the number down but rarely clears a hard week.
How much sleep is enough?
The American Academy of Sleep Medicine and the Sleep Research Society recommend that adults regularly get seven or more hours a night. Individual need varies; a practical test is how many hours you sleep after several days with no alarm. Use that number above.
Paying it back
- Spread it out. An extra thirty to sixty minutes a night for a week or two is easier on your body clock than one enormous lie-in.
- Move bedtime, not the alarm. Keeping the same wake time holds your rhythm steady, so the extra sleep comes from the evening end.
- Use naps carefully. A short early-afternoon nap can take the edge off without making it harder to fall asleep at night.
- Find the leak. If the same weeknights are short every week, the fix is in the evening routine on those days, not in the weekend.
This is arithmetic on your own numbers and general information, not medical advice. If you are regularly exhausted despite enough time in bed, or you snore heavily or stop breathing in your sleep, talk to a doctor.
Close the day in four minutes
Sleepward: Bedtime Routine is an iPhone and iPad app for the evening itself. Its listing describes a four-minute evening reset with a Brain Dump and tomorrow's three things, then personal time that ends before the bedtime you chose, and a darkening wind-down with white, pink or brown noise.
Get Sleepward on the App StoreFree to download with in-app purchases. Optional Pro adds more soundscapes and world content; check the App Store for current prices. Sleepward is a routine app, not a treatment, and this page is general information, not medical advice.
Honest Little Apps publishes both Sleepward and this page. This is a separate browser tool and does not sync with the app. App details checked November 10, 2026.
On a computer? Open it on your iPhone
