Is a sleep cycle exactly 90 minutes for everyone?

No, 90 minutes is a widely accepted average. Individual sleep cycles can range from about 70 to 120 minutes. This calculator provides a strong starting point. You can experiment with adding or subtracting 10-15 minutes from the suggested times to fine-tune it to your personal rhythm.

How much sleep do I need?

Most adults need 7 to 9 hours of sleep per night. This calculator provides wake-up times that correspond to completing 4 to 6 full sleep cycles, which falls within this healthy range (6 to 9 hours of sleep).

What if it takes me longer than 15 minutes to fall asleep?

The calculator uses a 15-minute average to fall asleep. If you know it typically takes you longer, you should adjust your bedtime accordingly. For example, if it takes you 30 minutes to fall asleep, go to bed 15 minutes earlier than the suggested time.

Sleep Calculator – Best Time to Sleep and Wake Up

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