Find the optimal bedtime or wake time based on 90-minute sleep cycles. Based on Australian sleep health guidelines.
The Sleep Health Foundation Australia recommends adults (18–64) get 7–9 hours of sleep per night. Teenagers need 8–10 hours, school-age children 9–11 hours, and older adults (65+) 7–8 hours.
Sleep occurs in cycles of approximately 90 minutes, moving through light sleep, deep sleep, and REM (dream) sleep. Waking at the end of a cycle (rather than mid-cycle) leaves you feeling more refreshed. Most adults complete 5–6 cycles per night (7.5–9 hours).