The best time to take a nap is early afternoon, roughly 6 to 8 hours after you wake up. For someone who gets up at 7 AM, that's about 1 to 3 PM. This lines up with the natural dip in alertness most people feel after lunch, so you fall asleep faster, and it's early enough that it won't make bedtime harder.
Free toolNap CalculatorWhen to set your alarm for a power nap or a full-cycle nap.Why early afternoon works best
Your alertness isn't flat through the day. Two things drive it: the sleep pressure that builds the longer you're awake, and your body clock, which runs on a roughly 24-hour rhythm. In the early to mid afternoon, rising sleep pressure meets a small dip in your body clock's alerting signal. That's the post-lunch dip. A heavy lunch can make it feel worse, but the timing comes mainly from your body clock.
Researchers have used this window for years in nap studies. In one Japanese study, people who were slightly short on sleep showed the classic mid-afternoon slump in mood and performance, and a short nap at 2 PM reversed it. An Australian study found that a 10-minute nap at 3 PM improved alertness and performance for up to about 2.5 hours afterward.
Your nap window by wake-up time
This is a rule of thumb, not an exact science. Early birds dip earlier, night owls later.
| Wake-up time | Best nap window |
|---|---|
| 5:00 AM | 11:00 AM to 1:00 PM |
| 6:00 AM | 12:00 PM to 2:00 PM |
| 7:00 AM | 1:00 PM to 3:00 PM |
| 8:00 AM | 2:00 PM to 4:00 PM |
| 9:00 AM | 3:00 PM to 5:00 PM |
Once you know when, the nap calculator tells you what time to set the alarm for a 20-minute or 90-minute nap.
Why not nap later in the day?
A nap lowers the sleep pressure you've built up since morning. Take it at 5 or 6 PM and you may not have enough left to fall asleep at your usual bedtime. That's one of the most common ways a nap backfires: you feel great at 7 PM, then lie awake at 11.
As a general guide, aim to be up from your nap by mid-afternoon, well before the evening. If you already have trouble falling asleep at night, keep naps short and early, or skip them for a while.
How long should the nap be?
Timing and length go together. In the early afternoon:
- 10 to 20 minutes is the sweet spot for most people. In the Australian study, 10 minutes gave the fastest boost, 20 minutes also helped, and 30 minutes caused a spell of grogginess before the benefits kicked in.
- About 90 minutes gives you a full sleep cycle, including deep sleep and REM. It's useful if you're paying back a short night, but it's more likely to affect bedtime. See is a 90-minute nap too long.
- Avoid 30 to 60 minutes if you need to be sharp right after. You're likely to wake up from deep sleep feeling worse than before.
Remember to add the few minutes it takes you to drift off when you set the alarm.
Best nap times for different situations
| Situation | Best time | Length |
|---|---|---|
| Regular 9-to-5 day | 1 to 3 PM | 10 to 20 min |
| Short night before | Early afternoon | 20 min, or 90 if you have time |
| Before a night shift | Late afternoon or early evening before work | Up to 90 min |
| Before a long drive | Just before setting off | 10 to 20 min |
| At work on a break | Middle of your lunch break | 10 to 20 min |
Night shift workers are the exception to the "not too late" rule, since your "night" is during the day. A nap before your shift can help you stay alert through it. For fitting naps into a workday, see napping at work.
Should you nap at all?
Naps are a good tool, but they aren't a fix for regularly short nights. If you need a nap every day to function, look at your night sleep first. Use the sleep calculator to find a bedtime that gives you 5 full cycles, and check how far behind you are with the sleep debt calculator.
If you're sleeping 7 to 9 hours and still can't get through the afternoon without dozing off, see a doctor. Excessive daytime sleepiness can be a sign of sleep apnea or another sleep disorder.