The short answer
10 minutes is the fastest recharge and the easiest to wake from. 20 minutes is the classic power nap. 30 minutes works if you are very tired, but you may feel groggy for a few minutes after. Past 30 minutes you are heading into deep sleep, and waking from it feels harder.
Why short naps work
When you fall asleep, you first pass through light sleep. Deep sleep comes later. Wake up in light sleep and you feel clear. Wake up in deep sleep and you feel heavy and slow. That heavy feeling has a name: sleep inertia.
A short nap keeps you in the light stage, so it is quick to get up from and does not steal sleep from your night.
Pick your length
- 10 minutes: a reset between tasks, or a lunch-break micro nap.
- 20 minutes: the mid-day slump. The default.
- 30 minutes: a bad night before, or a weekend. Allow a few minutes to come round.
- 90 minutes: a full sleep cycle. See the 90 minute nap guide.
Remember the time it takes to fall asleep
Most people do not fall asleep the moment they lie down. If you usually take five to ten minutes to drift off, a 20 minute timer gives you a 10 to 15 minute nap, and that is fine. If you tend to fall asleep quickly, a 20 minute timer is plenty.
Use a timer, with music that fades
Set the timer first, then close your eyes. That way you do not have to watch the clock. On this site the music fades in, fades out just before the end, and a soft chime wakes you. Start the 20 minute power nap, or choose 10 or 30.
Questions
Is a 10 minute nap enough?
Yes. Ten minutes of rest, even without full sleep, can take the edge off tiredness, and it is the easiest nap to wake up from.
Can a power nap be too long?
Yes. Past about 30 minutes you may fall into deep sleep and wake up groggy. If you are napping longer on purpose, aim for about 90 minutes, a full cycle.
Do I have to fall asleep for a nap to count?
No. Lying still with your eyes closed and your mind quiet is restful even if you never fully fall asleep.
General information, not medical advice. If you are very tired all the time, or nap a lot and still feel awful, talk to a doctor. The nap timer is a gentle wake-up, not a safety alarm: set a backup alarm.
