Sleep cycles
A wake time or bedtime from 90-minute cycles plus the minutes you need to fall asleep.
Open a calculatorSleep debt
Nightly gap is need minus hours slept. Total is that gap times the number of nights. A surplus (you slept more) comes out negative. Not a medical score.
h
h
Total gap
7.5 h
Per night
1.5 h
Total gap: 7.5 h
Catch-up sleep is messy. This only multiplies the gap. The cycle page is about bed and wake clocks.
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An educational estimate. Not medical, tax or credit advice.