Personal sleep planning

Sleep Calculator

Plan a bedtime or wake-up time around your age, sleep target, time needed to fall asleep and daytime naps. Compare alternatives and build a more consistent weekly schedule.

Plan your sleep

Choose what you already know, then adjust the recommendation to fit your routine.

Your sleep plan

Planned time–

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Overnight sleep–

Total daily sleep–

Time in bed–

Estimated cycles–

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The coloured arc represents estimated sleeping time. Real sleep stages cannot be predicted from clock time alone.

Age-based alternatives

These times use the lower, middle and upper values of the selected age range after subtracting daytime naps.

Evening and morning timeline

Weekly sleep consistency

Compare a usual weekday schedule with your weekend schedule. This is a routine comparison, not a medical score.

Weekdays

BedtimeWake-up time

Weekends

BedtimeWake-up time

Weekday sleep–

Weekend sleep–

Sleep midpoint shift–

Schedule consistency–

Nap planner

Choose a start time and a preferred duration to see when the nap ends.

Nap startsNap duration

Planned wake-up from the nap–

Save your plan

Your entries and calculations stay in your browser and are not sent by this calculator.

Sleep recommendations by age

Sleep needs change with age. The ranges below are general daily recommendations; individual needs and sleep quality also matter.

Age	Recommended sleep per day
0–3 months	14–17 h
4–12 months	12–16 h
1–2 years	11–14 h
3–5 years	10–13 h
6–12 years	9–12 h
13–17 years	8–10 h
18–60 years	7–9 h
61–64 years	7–9 h
65 years and older	7–8 h

Recommendations for children up to age 5 include naps.

What happens during sleep?

During a typical night, non-REM and REM sleep repeat in cycles. A cycle commonly lasts about 80–100 minutes, and most people have four to six cycles per night.

N1 – falling asleep

The transition from wakefulness to sleep. Muscles begin to relax and you can still wake easily.

N2 – stable sleep

Heart rate and body temperature fall, and sleep becomes more stable.

N3 – deep sleep

Deep non-REM sleep is concentrated more in the first part of the night and supports physical restoration.

REM sleep

REM periods generally become longer later in the night. Dreaming is common, but a calculator cannot know your personal REM duration.

Sources and responsible use

Age-based ranges follow CDC sleep recommendations, and the description of sleep cycles follows the NHLBI guide to sleep stages. The result is a planning estimate and does not measure sleep quality or diagnose a sleep disorder.

Persistent insomnia, loud snoring, breathing pauses during sleep or severe daytime sleepiness should be discussed with a qualified healthcare professional.

Sleep calculator FAQ

Is every sleep cycle exactly 90 minutes?

No. Cycle length varies during the night and between people. The calculator therefore shows a broad estimated cycle range rather than treating 90 minutes as exact.

Does time in bed equal time asleep?

Not necessarily. Time in bed includes the estimated time needed to fall asleep, while overnight sleep is the planned sleeping duration.

How are naps included for children?

For age groups whose recommendation includes naps, enter the expected daytime nap total. The calculator subtracts it when creating the overnight alternatives.

Can the calculator measure REM or deep sleep?

No. It can explain typical sleep stages, but personal stage timing requires appropriate sleep monitoring and cannot be derived from bedtime alone.

What does the weekly comparison show?

It compares sleep duration and the midpoint of sleep between weekdays and weekends to make schedule changes easier to notice.

Does this replace medical advice?

No. It is an educational planning tool, not a diagnosis or treatment recommendation.