The alarm that tells you to go to bed
Everyone sets the one that wakes them. The one that would actually decide how long they sleep is the one at the other end of the night, and it is a subtraction away.
Set a bedtime alarm for
9:45 pm
That leaves 30 minutes to put the day down, gets you into bed at 10:15 pm, asleep around 10:30 pm, and awake at 6:00 am after 5 cycles.
| Bedtime alarm | In bed | Cycles | Time asleep |
|---|---|---|---|
| 8:15 pm | 8:45 pm | 6 cycles | 9h |
| 9:45 pm | 10:15 pm | 5 cycles | 7h 30m |
| 11:15 pm | 11:45 pm | 4 cycles | 6h |
| 12:45 am | 1:15 am | 3 cycles | 4h 30m |
| Set the alarm for | Cycles | Time asleep |
|---|---|---|
| 12:00 am | 1 cycle | 1h 30m |
| 1:30 am | 2 cycles | 3h |
| 3:00 am | 3 cycles | 4h 30m |
| 4:30 am | 4 cycles | 6h |
| 6:00 am | 5 cycles | 7h 30m |
| 7:30 am | 6 cycles | 9h |
Why it is a separate number from the bedtime
An alarm that goes off at the moment you are supposed to be horizontal is an alarm you ignore, because at that moment you are downstairs with the lights on. The gap above is the difference between the alarm and the bed, and it is the part of this sum that is actually yours to set — the site has no view on how long it takes you to put the day down.
The cycle length and the drop-off allowance are the same two numbers used on every page here that counts cycles, and they follow you between pages. Move them on a wake page and this page will already agree with them.
The same sum, laid out differently
If what you want is a page you can keep, every wake time on the quarter hour has an address of its own. If the question is what to do about the screens before any of this, that is one more subtraction.