How long to nap

Wondering how long to nap so you wake up sharper rather than groggier? The short answer is 10 to 20 minutes for most people, or a full 90 minutes if you have the time. This guide explains why those two lengths work and the stretch in between does not. The timer above is ready to run, and the nap timer page loads 20 minutes by default. Also searched as best nap length, ideal nap time, power nap length.

This is general information, not medical advice. If you are often exhausted during the day, talk to a doctor.

What happens during a nap

Sleep moves through stages. The first minutes are light sleep (stage 1 and 2). Deep, slow-wave sleep (stage 3) usually begins somewhere around 20 to 30 minutes in. REM sleep, where most dreaming happens, follows later, and a full cycle through all stages takes roughly 90 minutes. How long you nap decides which stage you wake from, and that decides how you feel afterward.

Nap lengths compared

Length	You wake from	What you get
10 minutes	Light sleep	A quick lift in alertness, almost no grogginess
20 minutes	Light sleep	The classic power nap: alertness, mood, some memory benefit
30 to 60 minutes	Deep sleep	Risk of sleep inertia; you may feel worse for 20 to 30 minutes after waking
90 minutes	End of a full cycle	Deep and REM sleep, easier waking, helps with learning and creativity

Sleep inertia: the 30-minute trap

Sleep inertia is the heavy, slow feeling after waking from deep sleep. It can last from a few minutes to half an hour. A nap of 30 to 60 minutes often ends right in the middle of deep sleep. That is why a "quick" 45-minute nap can leave you feeling worse than no nap at all. Either stop before deep sleep begins, around 20 minutes, or sleep long enough to finish the cycle.

What the research says

A NASA study of pilots found that a nap of about 26 minutes improved performance and alertness on long flights. Many sleep researchers treat 10 to 20 minutes as the sweet spot for a daytime nap, because it delivers most of the benefit with the least inertia. Longer naps can help after a very short night, but they also make it harder to fall asleep that evening.

The best time of day

Early afternoon, roughly 1 to 3 pm, matches the natural dip in alertness most people feel after lunch. Napping later than about 4 pm starts to eat into your night sleep. If you work shifts, place the nap before the stretch where you are usually most tired.

The caffeine nap

Drink a cup of coffee, then lie down right away for 20 minutes. Caffeine takes about 20 to 30 minutes to kick in, so it arrives just as you wake, and the short nap clears some of the sleepiness on its own. People who struggle to fall asleep quickly often find this works better than coffee alone. Skip it in the late afternoon for the same reason as any late nap.

Who should keep naps short, or skip them

People with insomnia, because daytime sleep reduces the pressure to sleep at night.
Anyone who wakes from naps feeling worse: try 10 minutes, or none.
Night-shift workers may do better with a planned longer nap before the shift.

Try it

Start with the 20 minute timer or the nap timer, set Sound to Bell for a gentler wake-up, and lie down as soon as you press Start. For a full cycle on a weekend, the 90 minute timer is ready. If what you need is help winding down at night rather than a daytime nap, see the sleep timer.

Frequently asked questions

Is a 20-minute nap really better than 45 minutes?

For most people, yes. Twenty minutes stays in light sleep, so you wake up quickly. Forty-five minutes usually lands in deep sleep, and waking from it leaves you groggy for a while.

Does the nap timer include time to fall asleep?

Set it for the whole lie-down, including the drift-off. If you take ten minutes to fall asleep, a 20-minute timer gives you about ten minutes of actual sleep, which is still enough for a lift.

Can naps replace lost night sleep?

Only partly. A nap helps with alertness the same day, but it does not replace the deep and REM sleep you get across a full night. Keep working on night sleep first.