Sleep cycles
Find optimal wake-up times or bedtimes based on 90-minute sleep cycles plus the time you need to fall asleep.
Open calculatorSleep debt
Nightly sleep deficit equals your daily sleep need minus actual hours slept, multiplied across the selected number of nights.
h
h
Cumulative sleep debt
7.5 h
Deficit per night
1.5 h
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To plan optimal bedtime and wake-up times in 90-minute blocks, open the “Sleep cycles” calculator.
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Educational estimate only. Not medical, tax, legal or financial advice.