Our calculator uses the science of 90-minute sleep cycles to find your ideal bedtime or wake-up time — so you rise at the lightest phase of sleep, not the deepest.
Recommended bedtimes
Recommended wake-up times
If you fall asleep right now, these are the best times to wake up to complete full sleep cycles.
Best wake-up times if you sleep now
Your sleep isn't one long continuous state — it's a series of 90-minute cycles, each containing distinct stages that restore your body and mind.
Light sleep. You drift in and out, easily awakened. Lasts 5–10 minutes. Muscles relax, heart rate slows.
True sleep begins. Body temperature drops, heart rate slows, eye movement stops. Brain begins producing sleep spindles.
Hardest to wake from. Physical restoration, immune function, memory consolidation all occur here.
Dreaming occurs. Brain is active. Emotional processing, creativity, and learning are consolidated.
After ~90 minutes, the cycle restarts. Later cycles have more REM sleep. Waking at cycle end feels natural.
Everything you need to understand and improve your sleep, in one place.
Find the optimal nap duration to avoid sleep inertia. Power naps (20 min) vs full cycle naps (90 min) explained.
Try now →Track how much sleep you're missing and calculate how long it takes to recover your sleep debt.
Try now →Are you a morning lark, a night owl, or somewhere in between? Discover your chronotype and optimal schedule.
Try now →Enter your wake-up time and get the ideal bedtimes based on completing 4, 5, or 6 full sleep cycles.
Try now →Estimate how much REM sleep you're getting based on your total hours and sleep schedule.
Try now →See the recommended hours and best sleep windows based on your age group, from newborns to seniors.
View guide →Enter when you want to nap and get the best wake times.
How much sleep are you missing? Calculate your debt.
Answer a few questions to find your sleep chronotype.
Estimate your nightly REM sleep based on total hours slept.
See recommended sleep hours and best bedtimes for your age.
Rate your sleep habits to get a personal quality score.
Small, consistent habits make the biggest difference to sleep quality. Here are the top science-backed recommendations.
Go to bed and wake up at the same time every day, even weekends. This anchors your circadian rhythm, making sleep onset easier and morning wakeups natural.
The ideal sleep temperature is 65–68°F (18–20°C). Your body temperature must drop to initiate sleep. Blackout curtains help melatonin production.
Blue light from phones and computers suppresses melatonin for up to 2 hours. Switch to warm lighting or blue-light filters 90 minutes before sleep.
Caffeine has a half-life of ~5–6 hours. An afternoon coffee can still disrupt deep sleep even if you fall asleep easily.
30–60 minutes of calm activity before bed signals your nervous system that it's time to sleep. Reading, gentle stretching, or meditation all work well.
Regular exercise dramatically improves sleep quality and duration. But intense workouts within 3 hours of bedtime can raise core temperature and delay sleep onset.