What is a sleep cycle?

A sleep cycle is a complete progression through all stages of sleep, including light sleep, deep sleep, and REM sleep. Each cycle lasts approximately 90 minutes, and most adults need 5-6 complete cycles per night for optimal rest.

Why should I wake up between sleep cycles?

Waking up between sleep cycles, rather than in the middle of one, helps you feel more refreshed and alert. When you wake during a deep sleep phase, you're more likely to feel groggy and disoriented.

How long does it take to fall asleep?

On average, it takes about 15 minutes for a person to fall asleep. This calculator automatically accounts for this time when suggesting optimal bedtimes.

How many hours of sleep do I need?

Most adults need 7-9 hours of sleep per night, which equals 5-6 complete sleep cycles. However, individual needs may vary based on age, health, activity level, and other factors.

Sleep Calculator

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Each option includes 15 minutes to fall asleep

Sleep Science Explained

Fall Asleep Time

The average human takes 15 minutes to fall asleep. This calculator accounts for this time when suggesting your bedtime.

Sleep Cycles

A good night's sleep consists of 5-6 complete sleep cycles. Each cycle lasts approximately 90 minutes.

Perfect Timing

Waking up between cycles helps you feel more refreshed. Waking up in the middle of a cycle can leave you feeling groggy.

Quality Over Quantity

It's better to wake up after a complete cycle than to sleep longer and wake up mid-cycle. Quality matters!