Best bedtime calculator (when you have a fixed wake-up time)
If you must wake at a specific time, the best bedtime is often the one that lines up with a complete number of sleep cycles.
SleepRight gives you multiple options (typically 4–7 cycles) so you can choose the earliest realistic bedtime that still lands between cycles.
If you’re choosing between two options, many people prefer the one that avoids waking mid-cycle even if the total sleep time is slightly shorter.
Best wake-up time (when you know your bedtime)
If you know when you’ll go to bed, SleepRight suggests wake-up times by adding a fall-asleep buffer (default 15 minutes) and then stacking full cycles.
This makes it easier to find a wake-up time that feels smoother—especially if you’re using an alarm.
Sleep cycles explained (and why they matter)
A sleep cycle is a repeating pattern of sleep stages through the night. Many calculators use an average cycle length of about 90 minutes,
but cycles can vary by person and over the course of the night. That’s why SleepRight lets you adjust the cycle length—if you consistently feel better
with slightly shorter or longer timing, tuning this setting can make the recommendations feel more “you”.
How long does it take to fall asleep?
A common estimate is around 10–20 minutes, but your real number might differ based on stress, caffeine, screens, or your sleep routine.
If the results feel “off,” adjust the fall-asleep time to match your experience. For example, if you usually lie there for 30 minutes, set the buffer to 30.
Nap calculator (power nap vs full cycle nap)
A power nap (often 20–30 minutes) is popular because it’s short and many people wake with less heaviness.
A full-cycle nap (about one cycle) can work too if you have time—SleepRight shows both so you can pick what matches your day.
If you tend to feel terrible after naps, start with a shorter nap option and keep it consistent for a week.
Why you wake up groggy (sleep inertia)
That “hit by a bus” feeling is often called sleep inertia. It can be worse if you wake from deeper sleep.
Timing your alarm closer to the end of a cycle can help, but other factors matter too—sleep debt, alcohol, late caffeine, dehydration, and inconsistent wake times.
If you wake groggy most days, try stabilising your wake-up time first.
Shift work and unusual schedules
If your schedule is irregular, the most useful strategy is still the same: align sleep with cycles and keep your wake-up time consistent when possible.
Use SleepRight’s Bedtime → Wake mode after you know your “lights out” time, and aim for a cycle count you can realistically repeat across workdays.
Teens and kids: what changes?
Teen sleep timing often shifts later naturally, while school start times force early wake-ups—this mismatch is a big reason mornings feel rough.
SleepRight can help by finding the earliest bedtime that still lands on full cycles, and by making the trade-offs obvious (e.g., 5 cycles vs 6 cycles).
Consistency beats “perfect” timing
Many people chase the perfect bedtime once, but feel better when they keep the same wake-up time for weeks.
Use SleepRight to choose a bedtime you can repeat consistently, not just the most “ideal” number on paper.
Simple sleep tips that support the calculator
For better results from any sleep schedule: keep a consistent wake time, get bright light in the morning, keep caffeine earlier in the day,
and make your bedroom dark and cool. If you’re using naps, keep them short or full-cycle—avoid long random naps that leave you groggy.
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