Obenpaper

Try the numbers

Work backwards to bedtime

Set the time you have to be up and the hours you want. It counts back, including how long you take to drop off.

22:15lights out

To be asleep by 22:30 and awake at 06:30.

Start winding down
21:45
Lights out
22:15
Actually asleep
22:30
Time in bed
8 h 15 m

Plain arithmetic — wake time, less the hours you asked for, less how long you take to drop off. It makes no claim about what happens while you are asleep, and the right amount of sleep is the amount you wake up feeling well on.

Nothing you type here is sent anywhere or kept. Refresh the page and the boxes are empty again.