Sleep schedule (cycles)

Fix your wake or bedtime and see suggestions for 3 to 6 sleep cycles (~90 min, adjustable).

Your schedule

What to fix

I know when I want to wake up(suggests bedtimes)I know when I lie down(suggests wake times)

Time

Cycle and latency90 min per cycle · 15 min to fall asleep

Default: 90 min per cycle and 15 min to fall asleep. Adjust if you know your values.

Cycle length (minutes)

Time to fall asleep (minutes)

Your data is not stored. Everything runs in your browser.

Suggestions

--:--

Estimated duration

7 h 45 min

Suggested times by number of sleep cycles
Cycles	Estimated duration	Suggested bedtime
3	7 h 45 min	--:--
4	7 h 45 min	--:--
5	7 h 45 min	--:--
6	7 h 45 min	--:--

This is an educational planner, not a diagnosis or prescription for sleep. Cycle length and sleep latency vary by person and night. For persistent problems, see a health professional.

What are “sleep cycles” here?

Many popular articles describe cycles on the order of about 90 minutes from one sleep onset to the next, with variation by person and night. This page uses that as a simple clock: you enter how long you take to fall asleep and how long you treat one cycle; it suggests combinations with 3 to 6 cycles.

Adult sleep schedule and restful night habits

Want to situate this sleep schedule and use it better in your routine?Read the guide →

Why align wake or bedtime with cycles?

Some people feel better waking at the end of a cycle than in the middle. That is not a rule or a promise of perfect sleep; it is a way to explore schedules with clear, adjustable logic.

When it might help

Shift changes, big days ahead, experimenting with grogginess, or playing with scenarios. If you have insomnia, severe daytime sleepiness, or snoring with pauses, seek professional evaluation instead of relying on this.

Tips

Increase sleep-onset minutes if you usually lie in bed on a screen or ruminating.
If 90 minutes does not match your nights, change cycle length and compare suggestions.
Regular light, caffeine, and bedtime habits still matter more than any calculator.

Important limitations

Educational model with fixed assumptions. It does not measure real sleep, screen for apnea or other disorders, or prescribe how many hours you need. Persistent problems deserve a clinician.

Evidence-based context

Public health sources often describe full sleep cycles on the order of about 90 minutes (e.g. NHS UK) and typical ranges around 90–110 minutes (e.g. Sleep Foundation). Exact length varies. You can change cycle length and sleep-onset time to better match your situation.

What this tool computes

If you fix wake time: for each n cycles, suggested bedtime is wake time minus (sleep-onset minutes + n × cycle length). If you fix bedtime: suggested wake time is bedtime plus (sleep-onset minutes + n × cycle length).

total_min = sleep_onset_min + n × cycle_min
Bedtime ≈ wake_time − total_min (wake-fixed mode)
Wake ≈ bedtime + total_min (bed-fixed mode)Tmin⁡=s+n⋅ctbed≈twake−Tmin⁡twake≈tbed+Tmin⁡\begin{aligned}T_{\min}&=s+n\cdot c\\t_{\mathrm{bed}}&\approx t_{\mathrm{wake}}-T_{\min}\\t_{\mathrm{wake}}&\approx t_{\mathrm{bed}}+T_{\min}\end{aligned}Tmin​tbed​twake​​=s+n⋅c≈twake​−Tmin​≈tbed​+Tmin​​

Sources cited: NHS, How to get to sleep (cycles ~1 h 30); Sleep Foundation, What happens when you sleep (cycles ~90–110 min, vary).

FAQ

Is the suggested time exact for me?

No. It is an estimate from the minutes you configured. Your body, age, medications, and sleep quality vary. Treat it as a starting point, not a guarantee.

Does this treat insomnia or replace a doctor?

No. It is only arithmetic with simple assumptions. Sleep disorders need professional assessment.

Why 90 minutes by default?

It is widely used in public materials. Your cycle may differ. Adjust “cycle length”.