Sleep debt
Calculate how many hours of sleep you are short of your personal target across a run of nights.
Open calculatorSleep cycles
Models sleep in 90-minute cycles (light sleep, deep sleep and REM) and adds your sleep-onset latency (typically ~15 minutes). Waking up at the end of a completed cycle rather than mid-deep-sleep helps reduce morning grogginess.
min
4 cycles
05:15
5 cycles
06:45
6 cycles
08:15
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Educational estimate only. Not medical, tax, legal or financial advice.