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Sleep schedule planner

Bedtime or wake-up options for 7, 8 and 9 hours of sleep, allowing for time to fall asleep.

Free · No registration or payment

Calculation

Calculation mode

Result

7 h
23:45

Bedtime · Previous day

8 h
22:45

Bedtime · Previous day

9 h
21:45

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.

The result updates as you change the fields. Your data never leaves the browser.

Only upon clicking, current data is sent to generate the PDF and is not stored.

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

  • NHLBI. How Sleep Works: Sleep Phases and Stages
  • NHLBI. How Sleep Works: How Much Sleep Is Enough?
  • Hirshkowitz M et al. National Sleep Foundation's sleep time duration recommendations: methodology and results summary. Sleep Health, 2015

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.

How to use the calculation

1

Enter the starting values

Use actual values and the appropriate units.

2

Adjust the parameters

Adjust the starting assumptions for your situation.

3

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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For professionals

Calculation assumptions

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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What next

Formula breakdowns, biomarker reference ranges and nutrition articles with cited sources are in the NutriFit knowledge base.

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