Find the best bedtime or wake-up time using healthy 90-minute sleep cycles.
A sleep cycle lasts about 90 minutes and includes Light Sleep, Deep Sleep, and REM Sleep.
Waking up near the end of a sleep cycle usually helps you feel more refreshed than waking up during deep sleep.
Most healthy adults sleep best with 5 complete sleep cycles (about 7½ hours).
A sleep cycle is one complete sequence of Light Sleep, Deep Sleep, and REM Sleep. One cycle lasts about 90 minutes.
Although every person is different, the average sleep cycle is approximately 90 minutes. This calculator estimates the best bedtime and wake-up time based on complete cycles.
| Cycles | Sleep | Recommendation |
|---|---|---|
| 3 | 4h 30m | Too Little |
| 4 | 6h | Minimum |
| 5 | 7h 30m | ⭐⭐⭐⭐⭐ Recommended |
| 6 | 9h | Great for Recovery |
Most people don't fall asleep immediately after getting into bed. Adding 15 minutes gives a more realistic bedtime.