Sleep schedule planner
Bedtime or wake-up options for 7, 8 and 9 hours of sleep, allowing for time to fall asleep.
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Calculation
This calculation is for reference only and is not medical advice, a diagnosis or a prescription. If you have a medical condition, are pregnant, take medication or have any doubts, discuss the result with a physician or a qualified nutrition professional.
Result
- 7 h
- 23:45
- 8 h
- 22:45
- 9 h
- 21:45
Bedtime · Previous day
Bedtime · Previous day
Bedtime · Previous day
Most adults are advised to sleep 7–9 hours. These are schedule options, not an individual sleep prescription or a sleep-stage prediction. Sleep cycles and stages vary during the night. Clock times cannot guarantee waking during REM or an easy awakening.
How it is calculated
Wake time = bedtime + sleep onset time + sleep duration; bedtime is calculated by subtracting these intervals.
Formula
Wake time = bedtime + sleep onset time + sleep duration; bedtime is calculated by subtracting these intervals.
Limits of the method
Most adults are advised to sleep 7–9 hours. These are schedule options, not an individual sleep prescription or a sleep-stage prediction. Sleep cycles and stages vary during the night. Clock times cannot guarantee waking during REM or an easy awakening.
Sources of the method
How to use the calculation
Enter the starting values
Use actual values and the appropriate units.
Adjust the parameters
Adjust the starting assumptions for your situation.
Read the result
Consider the model limitations; a calculation is not a measurement.
Frequently asked questions
What does the calculation show?
Bedtime or wake-up options for 7, 8 and 9 hours of sleep, allowing for time to fall asleep.
What limitations apply?
Most adults are advised to sleep 7–9 hours. These are schedule options, not an individual sleep prescription or a sleep-stage prediction. Sleep cycles and stages vary during the night. Clock times cannot guarantee waking during REM or an easy awakening.
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