Nap timer
How long should you nap?
Nap length is not a preference. It decides whether you wake up clear or wreck your afternoon. Pick one of these four and we will start the timer.
10 minutes
The reset. Almost pure light sleep. You will feel sharper within minutes and there is essentially no grogginess to pay back.
20 minutes
The standard. The best general-purpose nap. Long enough to genuinely restore alertness, short enough that you stay out of deep sleep.
30 minutes
The edge. You are starting to touch deep sleep. Workable, but expect a few minutes of fog on the way out.
90 minutes
The full cycle. A complete cycle including REM. Wake at the end of it and you can feel better than after a short nap — but it costs ninety minutes and can push your bedtime later.
The rule that matters
Stay under thirty minutes or go the whole ninety. The dead zone between is where you get woken out of deep sleep, and that is the single most reliable way to feel worse after a nap than before it.
More on this in the power nap guide.
Common questions
Why is a 40 minute nap bad?
Because it is long enough to drop you into slow-wave deep sleep but too short to let you climb back out of it. Being woken mid-deep-sleep produces the strongest sleep inertia of any wake point — you can feel worse than if you had not napped at all, sometimes for half an hour.
What is a coffee nap?
You drink a coffee immediately before a twenty-minute nap. Caffeine takes roughly twenty to thirty minutes to reach peak effect, so it arrives just as you are waking. Some people find the combination noticeably better than either alone.
How late is too late to nap?
As a rule of thumb, stop napping about seven hours before your intended bedtime. Naps borrow from the sleep pressure that gets you to sleep at night, and a late one is a common hidden cause of insomnia.