How long should a nap be?

A good nap can be a legitimate performance tool. The trick is getting the length and timing right.

What research shows about nap length

A frequently cited 2006 study compared no nap with naps of 5, 10, 20 and 30 minutes in healthy young adults who were mildly sleep restricted.

• 5 minutes: little benefit.
• 10 minutes: improvements in alertness, fatigue and cognitive performance appeared immediately and lasted up to about 2.5 hours.
• 20 minutes: benefits appeared after about 35 minutes and lasted a similar time.
• 30 minutes: there was an initial period of grogginess before benefits appeared.

That grogginess is called sleep inertia. It's more likely when you wake from deeper sleep, which becomes more common as a nap gets longer.

Choosing a nap length

• 10–20 minutes (power nap): best for a quick alertness boost.
• About 60 minutes: may help memory consolidation but can leave you groggy.
• About 90 minutes: one full sleep cycle, useful after a short night but more likely to affect bedtime.

Timing matters

Nap in the early afternoon, when there's a natural dip in alertness. Late-afternoon or evening naps can reduce sleep pressure and make it harder to fall asleep at night.

When naps signal a problem

Adults need at least 7 hours of sleep per night. If you need a long nap every day, look at your night-time sleep first — see how much sleep adults need. Excessive daytime sleepiness despite enough time in bed is worth discussing with a clinician.

For more on sustaining energy through the day, visit our energy optimization guide and the sleep optimization hub.