Sleep latency is the amount of time it takes to fall asleep. Normal is considered to be 15-25 minutes (some say 30minutes). I’ve had many people tell me with disappointment that it takes them 30 minutes to fall asleep and how they know people who can fall asleep instantaneously. They are surprised to hear that 30 minutes falls into the normal range.
In fact, a sleep latency of less than 5 minutes is considered to be a sign of sleep deprivation. So, if you can go into a dark room and fall asleep within 5 minutes – this isn’t necessarily a good thing and could mean you need more sleep.