How much sleep do you owe, and how do you pay it back?
Seven nights in, a debt out, and a recovery plan that adds sleep in small pieces instead of one heroic weekend. Built for rotating shifts, works for everyone else.
Your numbers
Hours actually slept, last 7 nights
Result
Sleep debt this week
0 hours
Recovery plan
Part of Body Kit, a free appSave your details once and all 7 tools fill themselves in. Installs to your phone, works offline, nothing leaves your device.Open What sleep debt is, and is not
Debt is the gap between what you need and what you got, added up. A week at 6 hours when you need 7.5 is 10.5 hours down, which is more than a full night. What debt is not: a bank account you can refill with one 12-hour sleep. Research on recovery sleep shows performance stays impaired for days after a short-sleep stretch, even when the hours look repaid.
Why the weekend does not fix it
Sleeping until noon on Saturday shifts your body clock later, which makes Sunday night's sleep worse, which makes Monday the most tired day of the week. The plan the tool gives adds 30 to 60 minutes a night across the week and uses short naps, because that recovers debt without moving the clock.
Shift workers, specifically
Night shift debt piles up faster because daytime sleep is lighter and shorter. Two things help more than anything: a dark, cool, quiet room treated as seriously as a night sleeper's, and a 20 to 30 minute nap before the shift or on a break. The rotating-shift plan protects the sleep on the day you switch, which is the one that usually goes missing.
Sleep debt is a simple model: need minus actual, summed. Real recovery is not one-for-one and takes days to weeks. Persistent short sleep, loud snoring, or falling asleep at the wheel are reasons to see a doctor. General information, not medical advice.