 [ Symptoms ] what should my bedtime be for a good night is sleep [ Disease ] i have a formula that people can use the formula is basically this take a 90 minute segment and count back five 90 minute segments from when your scheduled wake up time is and that should probably be about when you should go to bed pick your wakeup time so let is say it is 700 am then we know the average sleep cycle is somewhere between 80 and 90 minutes so you want to count and we know you need about 5 of those so count backwards for 5 ninety minutes segments from 700 am and you would get i believe it is 1130 okay that is how you can really tell if you are refreshed or sleep deprived things of that nature because if you are not getting that individualized sleep number as it were that is when you are going to feel it there is a myth going on out there that we all need eight hours of sleep and i am here to tell you that is absolutely not true there is no perfect sleep number out there for everyone everyone is number is a bit individualized and so what we have learned from the data basically is when you wake up and feel refreshed look back and see how many of hours of sleep you got and that is probably your sleep number