How to know downtime?

Question

Since 'How can I make myself get enough sleep?' is on topic, I hope this one is too.

How to know how long I slept last night? or at least if I'm sleeping enough.

I keep track of when I go to bed and when I get up which is an upper bound for the time between falling asleep and waking up. Sometimes I feel like I've just been tossing and turning all night long without actually falling asleep.

• go to bed = physically going onto bed
• get up = physically getting off bed
• fall asleep = unconcious and dreaming
• wake up = concious and thinking

Answer 1

While the evidence for accuracy is disputed, there are apps that will track your sleep via exercise bands and/or your phone's sensors. Fitbit has one tied to their bands, and Sleep as Android can use your phone (set on your bed to catch vibrations) or a variety of fitness bands and such equipment. Depending on the sensors available, they may track movement via movement of the band or vibration of the bed, noise including snoring or talking in your sleep, or heartrate. Upon waking, the apps will generally give a record of how much time they believe you slept, as well as a breakdown of sleep cycles.