What are the stages of sleep?

Understanding the Sleep Stages

The tracker categorizes sleep into four stages:

  • Awake
  • REM
  • Light
  • Deep

Awake time

The time spent awake while in bed. It includes the time spent falling asleep and any wake-ups during the sleep session but excludes time you were out of bed or otherwise undetectable by the sensor. Short Awake segments during the night are common and generally not remembered by the sleeper.


REM sleep

REM stands for ‘Rapid Eye Movement’ and tends to be concentrated in the second half of the night. Critical to great sleep, REM sleep is associated with dreaming and long term memory.


Light sleep

Typically makes up the majority of your total sleep. While not as important as REM and Deep sleep it’s still an important component of the sleep cycle and general wellness.

Deep sleep:

Deep sleep is predominant in the first half of your sleep and is critical for overall recovery and long term health. This stage is most affected by your sleep hygiene and behaviors before going to bed since it occurs early in your sleep.

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