Sleep Debt Calculator
Hours you need, hours you got, and how many nights. The total is how far behind that leaves you.
Question 1 of 3
An estimate from what you report. It does not measure your sleep, and it is not medical advice.
What sleep debt means here
Sleep debt is the gap between the hours you meant to get and the hours you did get, added up over recent nights. Need 8, sleep 6, and do that for a week: 2 hours short, times 7 nights, is 14 hours behind.
The hours-you-need question starts at 8. Change it if you already know your number. Nights starts at 7, a typical week. After the last question, the result is how many hours behind that leaves you. Sleeping at least what you need leaves the total at 0.
Closing the gap
Pay it back slowly. About an extra hour a night is easier to keep than one very long sleep. If the debt is more than 5 hours, a weekend lie-in will not clear it. This is still an estimate from what you type in. It is not a reading of your nights, and it is not medical advice.
Frequently Asked Questions
How do you calculate sleep debt?
Subtract the hours you have been sleeping from the hours you need, then multiply by the number of nights. If you need 8 and you have slept 6 for 7 nights, the debt is 14 hours. If you slept at least what you need, the debt is 0.
Can I pay off sleep debt in one night?
A single very long sleep is a poor way to close a large gap. An extra hour a night spreads the catch-up out. A weekend lie-in will not clear a debt of more than a few hours.
What if I do not know how much sleep I need?
The hours-you-need field starts at 8, a common adult middle. For a figure based on age, use the how much sleep calculator, then come back and change the 8.
Is sleep debt a medical measure?
No. This is an estimate from the hours you report. It does not record your sleep, and it is not a diagnosis. Ongoing exhaustion, gasping at night, or sleepiness while driving is a reason to talk with a doctor.
Not sure about the hours you need? See a figure for your age.