Sleep Calculator

Discover your optimal bedtime or wake-up time based on sleep science

Bedtime Calculator

Calculate when you should go to bed if you want to wake up at a specific time:

Wake-up Time Calculator

Calculate when you should wake up if you go to bed at a specific time:

Understanding Sleep Cycles

Sleep occurs in cycles of about 90 minutes each, consisting of different stages:

1
Stage 1 (N1): Light sleep, transition between wakefulness and sleep (1-5 mins)
2
Stage 2 (N2): Body temperature drops, heart rate slows (10-25 mins)
3
Stage 3 (N3): Deep sleep, hardest to wake from (20-40 mins)
4
REM Sleep: Dreaming occurs, brain activity similar to wakefulness (10-60 mins)

Waking up at the end of a sleep cycle (when you're in lighter sleep) helps you feel more refreshed than waking during deep sleep.

Benefits of Quality Sleep

Getting enough quality sleep at the right times is essential for:

Improved Memory

Sleep helps consolidate memories and improve learning

Heart Health

Reduces risk of heart disease and stroke

Weight Management

Helps regulate hormones that control appetite

Mood Regulation

Reduces stress, anxiety, and depression risk

Tips for Better Sleep

Consistent Schedule

Go to bed and wake up at the same time every day, even on weekends

Limit Screen Time

Avoid screens 1 hour before bedtime (blue light disrupts melatonin)

Watch Caffeine

Avoid caffeine after 2pm as it can stay in your system for 6-8 hours

Cool Environment

Keep bedroom temperature between 60-67°F (15-19°C) for optimal sleep

Sleep Calculator FAQs

The calculator provides several options based on complete sleep cycles (each ~90 minutes). Waking at the end of a cycle (lighter sleep) helps you feel more refreshed than waking during deep sleep. The times shown represent 4, 5, or 6 full sleep cycles from your bedtime.

While individual sleep patterns vary, the calculator is based on average sleep cycle duration research. Most adults complete a sleep cycle in 90 minutes, though this can range from 80-110 minutes. The "minutes to fall asleep" adjustment helps personalize the calculation.

The National Sleep Foundation recommends:
  • Teenagers (14-17): 8-10 hours
  • Young adults (18-25): 7-9 hours
  • Adults (26-64): 7-9 hours
  • Older adults (65+): 7-8 hours
Individual needs may vary based on genetics, lifestyle, and overall health.