Sleep Calculator

When should you go to bed? Our sleep calculator determines the optimal bedtimes based on 90-minute sleep cycles, so you wake up feeling refreshed.

When do you need to wake up?

Or select a profession:

Recommended Bedtimes

Click "Calculate" to see your optimal bedtimes.

🌙 What is a sleep cycle?

A sleep cycle lasts about 90 minutes and consists of different sleep stages: light sleep, deep sleep, and REM sleep (dream phase). Waking up between cycles makes you feel more refreshed than waking up during deep sleep.

⏰ How much sleep do I need?

Adults need 7-9 hours of sleep per night. This corresponds to 5-6 complete sleep cycles. Regularly sleeping less than 6 hours increases the risk of health problems.

Sleep Cycles Visualized

Cycle 1
90 min
Cycle 2
90 min
Cycle 3
90 min
Cycle 4
90 min
Cycle 5
90 min
Cycle 6
90 min
Fall asleep 1.5h 3h 4.5h 6h 7.5h 9h

Curious when others wake up?

Discover the wake-up times of over 120 professions!

View All Jobs

Embed This Sleep Calculator

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  src="https://wann-muss-ich-aufstehen.de/en/sleep-calculator-embed/"
  width="100%"
  height="370"
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  title="Sleep Calculator – Calculate Your Optimal Bedtime"
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