Ideal Range
10-20 minutes is ideal. Falling asleep instantly suggests sleep debt.
Related Metrics
What is Sleep Latency?
Sleep latency is the time it takes you to fall asleep after getting into bed and attempting to sleep. It's measured from 'lights out' to the first epoch of sleep.
Why Sleep Latency Matters
Optimal sleep latency indicates proper sleep pressure and circadian alignment. Too short (<5 minutes) suggests sleep deprivation. Too long (>30 minutes) indicates insomnia or circadian misalignment.
How to Improve Sleep Latency
Common Mistakes
- Using phones/tablets in bed (blue light + mental stimulation)
- Going to bed before you're actually tired
- Caffeine too late in the day
- Exercising within 2-3 hours of bedtime
- Ruminating on the day's events in bed
The Science
Sleep latency is influenced by two processes: Process S (sleep pressure from adenosine buildup) and Process C (circadian alertness). When these align - high sleep pressure plus circadian dip - you fall asleep quickly. Caffeine blocks adenosine receptors, reducing sleep pressure. Light exposure influences your circadian clock. The goal is to align both processes to your desired bedtime.
Other Sleep Metrics
Deep Sleep
Deep sleep, also called slow-wave sleep (SWS) or N3 sleep, is the most restorati...
Ideal: 1.5-2 hours (15-25% of total sleep) for
REM Sleep
REM sleep is characterized by rapid eye movements, vivid dreams, and temporary m...
Ideal: 1.5-2 hours (20-25% of total sleep) for
HRV
Heart Rate Variability measures the variation in time between heartbeats. Higher...
Ideal: Highly individual - track your personal
Sleep Efficiency
Sleep efficiency is the percentage of time in bed that you actually spend sleepi...
Ideal: 85-95% for healthy adults. Above 95% mig