The best number is calculated by taking 100-(the hours you have until the alarm goes off)x(the wakeup call in local time). All numbers rounded down.

Example - 6 hours of sleep x 5am wakeup call = 30.
100-30 = 70. So your ideal sleep number is 70.

But if you're still tossing an hour later, it's 100-(5x5) = 75, so you have to fumble in the dark to find the controls.

Or just grind one out and it doesn't matter.

The real question is... what is Honey Badger's Sleep Number?