Health
Sleep Calculator: Optimal Times
Calculate best sleep and wake times.
Understanding sleep cycles helps wake refreshed.
Cycles
~90 min each: light→deep→REM. Need 4-6 cycles.
Recommended
- Adults: 7-9 hours
- Teens: 8-10 hours
Tips
Consistent schedule. Dark room. No screens 1hr before bed.
Frequently Asked Questions
How many cycles?
4-6 (6-9 hours). Each ~90 min.
Why tired?
Waking during deep sleep causes grogginess.
6 hours enough?
Most need 7-9. Chronic 6hrs causes sleep debt.