Sleep Calculator
How to Use?
- 1
Choose your calculation
Select whether you want to find bedtime or wake‑up time.
- 2
Enter your reference time
Enter your bedtime or wake‑up time.
- 3
Select sleep cycles
Choose how many 90-minute cycles you want (4–6).
- 4
View the result
The calculator shows the optimal target time and total sleep hours.
Worked Examples
If you go to bed at 22:00, when to wake after 5 cycles?
Given:inputs
calculateFor:wakeup
referenceHour:22
referenceMinute:0
sleepCycles:5
Result:calculated
timeStr:07:44
FAQs
1.Why 90 minutes?
+A typical sleep cycle (light, deep, REM) lasts about 90 minutes.
2.What about the 14 minutes?
+It takes most people around 14 minutes to fall asleep.