Sleep Debt Calculator
Every hour of sleep you miss adds up. See how much sleep debt you are carrying, and what it takes to pay it back.
Your sleep
Your sleep debt
Sleep debt does not just disappear. The most reliable way to pay it down is a consistent wake time, which means not sleeping through your alarm.
What is sleep debt?
Sleep debt is the running total of sleep you owe your body. If you need eight hours but average six and a half, you fall an hour and a half short every day, and that shortfall accumulates across the week. Small nightly gaps add up to the equivalent of missing entire nights of sleep each month.
You cannot fully repay a large sleep debt with one long weekend lie-in. Sleeping in also shifts your body clock later, which makes Monday harder. The reliable fix is a consistent wake time that slowly closes the gap.
The catch is that a consistent wake time only works if you actually get up. Last Alarm makes that non-negotiable, so your recovery plan does not die at the snooze button.