Wellness
Wake time from a bedtime
The same relationship rearranged, for when you are going to bed now and want to know when the cycle ends.
The Formula
wake = bedtime + 15 + 90 x cycles
The same relationship rearranged, for when you are going to bed now and want to know when the cycle ends.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| t_wake | Wake time | clock time | When the cycle finishes and you would wake naturally. |
| t_bed | Bedtime | clock time | When you get into bed. |
| n | Cycles | cycles | Number of 90 minute cycles, usually four to six. |
What Each Symbol Means
t_wakeclock time
Wake time
When the cycle finishes and you would wake naturally.
t_bedclock time
Bedtime
When you get into bed.
ncycles
Cycles
Number of 90 minute cycles, usually four to six.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate the best time to sleep page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate The Best Time To Sleep, filed under Health. Every number the guide produces comes from substituting into this one line.