If I go to bed at 9:00 PM, what time should I wake up?
Falling asleep around 9:15 PM, the best wake-up times are 4:45 AM (5 cycles) or 6:15 AM (6 cycles), so your alarm lands at the end of a 90-minute cycle.
Best wake-up times after a 9:00 PM bedtime
| Wake up at | Cycles | Total sleep |
|---|---|---|
| 6:15 AM — best | 6 | 9 hours |
| 4:45 AM | 5 | 7.5 hours |
| 3:15 AM | 4 | 6 hours |
These assume about 15 minutes to fall asleep, so you are actually asleep by 9:15 PM. A 4:45 AM alarm completes 5 full cycles for a standard work morning; 6:15 AM completes all 6 for the fullest night.
How long is sleep from 9:00 PM?
From a 9:00 PM bedtime, five 90-minute cycles plus the time to fall asleep brings you to 4:45 AM (about 7.5 hours of sleep), and six cycles to 6:15 AM (about 9 hours). Four cycles gives a shorter 3:15 AM wake-up (~6 hours) if you have to be up early. Lining the alarm up with the end of a cycle is what keeps the morning from feeling groggy.
Making 9:00 PM work as a bedtime
9:00 PM is an easy bedtime to keep consistent. For the best results, dim screens for the hour before, keep the room cool and dark, and wake at the same cycle-aligned time each day so your body clock locks in. If you need an exact target wake-up instead, use the wake-up pages to count backward to the right bedtime.
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