What if this was taken one step further and integrated with an alarm app for your phone? That would be a more useful implementation of this idea to me than a web page would be.
You could provide a time range of 60 to 90 minutes of when you need to get up, then press a button on the app to "set" it when you go to bed. The alarm could then figure out when the best time would be for you to get up in your provided time range.
Granted this assumes your audiences bed time varies from day to day, which probably isn't the best for someone trying to get the best sleep in the first place.
You could also do the reverse, set a wake-up time and have an alarm go off as a reminder for upcoming bedtimes...
You could provide a time range of 60 to 90 minutes of when you need to get up, then press a button on the app to "set" it when you go to bed. The alarm could then figure out when the best time would be for you to get up in your provided time range.
Granted this assumes your audiences bed time varies from day to day, which probably isn't the best for someone trying to get the best sleep in the first place.
You could also do the reverse, set a wake-up time and have an alarm go off as a reminder for upcoming bedtimes...