How is sleep efficiency calculated?

[KBiz]

I am wondering how accurate the sleep reports are?  Specifically, how is Sleep Efficiency calculated?  I see a sleep doctor and I want to show him my reports.  I just don't know if this is an accurate device to use as a true indicator of my sleep cycles.

[SteveH]

The following link gives some good info on sleep and the efficiency calculation:

https://help.fitbit.com/customer/portal/articles/1230068-about-sleep-tracking

[MatthewFitbit]

Per Steve's link above, the formula for sleep efficiency is:

time asleep / (total time in bed - time to fall asleep)

This is simply the amount of time you were asleep (and not restless) divided by the time you spent in bed after initially falling asleep.

[lactroi]

I am wondering how accurate the sleep reports are?  Specifically, how is Sleep Efficiency calculated?  I see a sleep doctor and I want to show him my reports.  I just don't know if this is an accurate device to use as a true indicator of my sleep cycles.

[HH-SJ]

My sleep dashboard just shows: Sleep duration, fall asleep, times of restless, times of awake and time(min) awake/restless.

How to calculate sleep efficiency from record provided by Dashboard?

Thanks

[NellyG]

@lactroi  I have moved your post to another topic where your question is answered. Let us know if you have more questions.

[john-is-my-name]

"How to calculate sleep efficiency from record provided by Dashboard?"

I am in the same boat. It seems to be implied that there is a sleep-score that is displayed somewhere. It is easy enough to calculate out the fitbit fomula of what time FitBit says I was asleep - the time I went to bed to get that number of minutes. My average in-bed time is about 5.5. hours. It takes about 10 minutes for me to go to sleep. If I divide that 10 mins. by the remaining 320 minutes (5 hrs and 20 minutes,) , I get 10/320 = 3% inefficiency and 97% efficient sleep. 

I'd love to make this more complicated (I do this a lot in life!)

What if used my total awake time from fitbit instead?  According to FitBit, my average awake time is 13% - 48 minutes a night. While this is within the average range for FitBit users of my gender and age, I do not believe I spend that much time at night awake. This leads me to believe that the FitBit sleep algorithm does not fit me well. 

[john-is-my-name]

I have revised my sleep efficiency calculation as follows;

1. From your sleep chart, add-up your 'humps' when you were awake, In the image file, The hump I have selected is from (1:24 - 1:32 - 8 min) . The sum of these humps ignores the 'dots' of 1 minute awake times, which I consider to be movements I make whilst still asleep.

2. Divide the sum from step #1 from your "time asleep" (, which is really your time in bed with intent to sleep).  Multiply this decimal by 100 for a percentage. The result is a percentage of your time awake to your time with intent to sleep.

3. Subtract the percentage from step #2 from 100. The result is the time that you were actually asleep to your your time with intent to sleep. 

I find this useful as it shows me how efficient my allocated sleep time is.  My average "time with intent to sleep" is 5.5 hours a night.  Using this method my sleep efficiency is always over 95%.  

Why sleep longer when you can sleep better for shorter durations?  🙂

[Ginam800]

To calculate sleep efficiency:

time asleep/time asleep + time restless/awake * 100

ex: a person is recorded to have spent  6 hrs 13 mins asleep and 2 hours and 37 mins restless/awake, which amounts to 8 hours and 50 mins totally in bed. Therefore converting to minutes and inputting numbers into the formula yields 373/530 * 100 = 70%

A sleep efficiency of 85% or higher has been determined to equate to a good nights rest. While it is recommended that a person should get 7-9 hours of sleep, quantity does not always equal quality. 

[haohao]

Hi all! 
I own a fitbit sense and I notice that the way sleep efficiency is calculated for the different type of sleep tracking (stages vs classic) is different. Does anyone know how is it calculated for each type of sleep tracking?