Chronotypes Explained: What The Research Shows
Quick Answer: A chronotype is your natural preference for when to sleep and be active. Large studies show it falls …
Sleep Blog
The Sleep Calculators Online blog covers sleep science, sleep health and practical ways to sleep better. Articles explain how sleep stages and REM sleep work, why trouble falling asleep and waking at night happen, how your body clock shapes when you feel sleepy, and what sleep disorders such as sleep apnea, narcolepsy and restless legs look like.
Updated articles link to the research and health sources behind them, and many pair with a free tool such as the bedtime calculator, the sleep cycle calculator or the sleep debt calculator.
Looking for something specific? Browse sleep guides by topic, all sleep calculators or our pillow reviews. The newest articles are below.
Circadian Rhythm Explained: How Your Body Clock Works
A circadian rhythm is your body’s roughly 24-hour cycle of physical, mental and behavioral changes. Internal clocks run it, and …
Sleep Deprivation: Signs, Effects And How To Recover
Sleep deprivation is what happens when you do not get enough sleep. It is one part of a wider problem …
What Is Sleep Debt? What The Research Shows
Quick Answer: Sleep debt is the gap between the sleep your body needs and the sleep you actually get, added …
How Much Sleep Do You Need? Hours By Age And Lifestyle
Most adults need at least 7 hours of sleep a night. The American Academy of Sleep Medicine and the Sleep …
Dreams Explained: Why We Dream, Dream Recall And Nightmares
Dreams are the images, thoughts and feelings you experience during sleep. Everyone dreams, for about two hours a night, but …
How Sleep Works: Pressure, Stages, Cycles And Dreams
Two systems control sleep. Sleep pressure builds the longer you are awake, partly as a brain chemical called adenosine accumulates. …
Waking Up At Night: Causes And What The Research Shows
Quick Answer: Waking up during the night is common, and the time you spend awake after falling asleep tends to …
How To Fall Asleep Fast: What The Research Supports
Quick Answer: No trick has been proven to put you to sleep in minutes, but several habits have evidence behind …
CBT-I Explained: How Cognitive Behavioral Therapy For Insomnia Works
CBT-I (cognitive behavioral therapy for insomnia) is a structured, drug-free treatment that changes the habits and thoughts that keep you …