😴 Perfect Nap Length — Sleep Cycle Optimizer

Avoid grogginess by waking in light sleep. Choose a power nap (10–20 min) or a full cycle (~90–110 min). Start now or schedule a nap, and tweak fall-asleep latency, chronotype, and caffeine.

Your Nap Plan

Leave “blank” to use now.
Adjusts recommended windows slightly.
May lengthen fall-asleep time a bit.
Educational only · listen to your body

Suggested wake-up times

Best targets to reduce sleep inertia:
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We aim for light sleep (~10–20 min) or whole cycles (~90–110 min) after your fall-asleep time.
Light sleep / REM (easier wake) Slow-wave zone (groggy if woken) Suggested wake

How to pick the perfect nap length (friendly science)

The “best” nap is usually one of two shapes: a power nap (about 10–20 minutes of actual sleep) or a full sleep cycle (roughly 90–110 minutes). Power naps keep you in lighter stages so you wake up clear-headed for the next few hours. Full-cycle naps take you down through deeper stages and back up toward REM, which also makes waking easier. The trouble zone is the middle: if you wake during slow-wave sleep (often around the 30–60 minute mark), you can feel heavy and foggy for a while—a feeling called sleep inertia.

This tool asks how long you usually take to fall asleep (called sleep latency) and then adds that to the timer, so a “20-minute” power nap really means “20 minutes after you nod off.” You can nudge timing for your chronotype (early bird vs night owl) and recent caffeine, both of which can shift how quickly you doze and how deep you go. We also let you plan from a start time or work backward from a must-wake deadline. Results show a few wake-up targets with a light traffic-light risk for grogginess.

A few friendly tips: set an alarm you like, keep naps earlier than late afternoon if possible, and try a glass of water and a patch of daylight when you wake. If you’re seriously sleep-deprived, you may drop into deep sleep sooner; in that case, aim either shorter (10–15 minutes) or commit to a full cycle. And remember, this is an educational wellbeing tool, not medical advice. If you struggle with insomnia, daytime sleepiness, or loud snoring, please talk to a healthcare professional. Your body is wonderfully adaptive—use these targets as gentle guideposts, then adjust to what makes you feel best.

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