Nap Length: How Long Should You Nap to Feel Refreshed

Napping is a bit of a lost art in today's society, but there is no question that most of us have something to gain from a little midday sleep. Whether you're looking to boost alertness, improve cognitive performance, or recover from sleep debt, understanding the optimal nap length can help you feel refreshed rather than groggy. This guide breaks down the science of napping, explores different nap durations and their effects, and shows you how to time your naps for maximum benefit.

How long should you nap for?

The optimal nap length can vary from person to person for any number of reasons—age, career, lifestyle, schedule, etc. However, the general consensus is that either a short power nap (10-20 minutes) or a full sleep cycle (about 90 minutes) is best. Below we'll explain why this is the case, take a look at the benefits of napping, and help you figure out what works best for you.

The science of napping and your sleep cycles

To understand why nap lengths vary, it helps to know what happens when you sleep. Your body moves through several sleep stages—light, deep sleep (also called slow wave sleep), and REM. A short, 10-20 minute nap keeps you in the lightest stage of sleep, making it easy to wake up feeling refreshed.

Longer naps allow you to enter deep sleep, which is restorative but can lead to grogginess—known as sleep inertia—if you wake up during it. A full 90-minute nap allows you to cycle through all stages, including REM, which is important for memory and cognitive function.

Choosing your nap length: from power naps to full sleep cycles

Your ideal nap length depends on your goal and how much time you have available.

Most of us trend towards quick power naps, simply because they are easier to fit into our daily routine. A 2006 study published by the Sleep Research Society found that 10-minute naps improved the participants' subjective sleepiness and cognitive performance, and were the "most effective afternoon nap duration" of the lengths they examined. Naps that were 20 minutes long produced similar results as well.

The National Sleep Foundation also states that "most people feel refreshed after a nap that lasts approximately 20 minutes." Why is a 20-minute nap good for you? When you first fall asleep, your body goes through a stage of light sleep.

Naps that are 20 minutes or less tend to keep you in this stage, which makes it much easier to wake up without feeling groggy. On the other hand, napping for less than 10 minutes is usually not enough to see any of the benefits of sleep. If you only have a few minutes available to rest, you're probably better off practicing mindfulness or meditation instead of trying to nap.

Naps in the 30-60 minute range present a tradeoff. In this case, you may actually end up feeling more tired and less alert than before you went to sleep. Following light sleep your body enters deep sleep, and being woken during this stage leads to sleep inertia, a state of sluggishness and disorientation.

The effects of sleep inertia are even worse when you are sleep deprived, which is likely the reason you're taking a nap in the first place. However, you will not see any of the cognitive benefits of sleeping from a short nap that only includes light sleep. In order for that to happen, you need to get at least a few minutes of deep sleep.

Additionally, research has shown that naps which include deep sleep but not REM sleep (deep sleep vs. REM sleep) will improve declarative memory tasks (mental things like remembering something and repeating it back), but will not improve procedural memory tasks (physical things like performing a specific activity). Typically you have to be asleep for about 90 minutes in order to reach REM sleep.

For most people, 90 minutes is the length of a full sleep cycle, which allows you to spend time in each stage of sleep (light, deep and REM, in that order). If you're sleep deprived (meaning you failed to get all the sleep your body needed the night before), napping for 90 minutes and cycling through every stage of sleep is the best way to feel rested and rejuvenated afterwards.

What about naps longer than 90 minutes? Not necessarily a problem, depending on how sleep deprived you are or how much your body may need to recover from physical activity. But, if you nap for much longer than this there's a good chance it's going to disturb your circadian rhythm.

What you do not want to happen is to have trouble falling asleep at night because you napped for too long during the day. If your nighttime sleep is negatively affected by your nap, you won't be any better off the next morning.

The benefits of a well-timed nap

Naps enhance performance, both mental and physical. For athletes, things like reaction time improve, and in the corporate world your cognitive abilities are heightened. Additional nap benefits include:

• Better mood
• Increased alertness
• Greater ability to learn
• Relaxation
• Reduce fatigue
• Lower nightly sleep need
• Help prevent high blood pressure

When is the best time of day to nap?

Timing is just as important as duration. The best time to take a nap is usually in the mid-afternoon, when your body naturally experiences a dip in energy. This is often between 1 p.m. and 3 p.m., when your body temperature drops and it produces more melatonin.

Napping during this window aligns with your body's circadian rhythm and is less likely to interfere with your nighttime sleep. Ideally you should nap as close as possible to the mid point between your usual wake and bed times. Avoid napping too late in the day, as taking a long nap in the evening close to bed time will almost certainly make it difficult for you to fall asleep at your regular bedtime.

Unfortunately for many of us, getting in even a 10-minute afternoon nap is often impossible during the typical work day. If you can't nap, try going outside for a bit and letting the sunlight hit your body, or a brief non-sleep deep rest session instead. This will inhibit production of melatonin and help you feel energized.

How WHOOP helps you nap smarter

Meeting your nightly sleep need is often a difficult task. A nap during the day (regardless of how long it is) helps reduce the amount of sleep your body requires at night. Based on previous sleep and strain you have accumulated, WHOOP calculates exactly how much sleep you should get each night in order to optimize your recovery the next morning.

When you take a nap, the WHOOP Sleep Planner incorporates it into the equation and adjusts accordingly the time it recommends you spend in bed that night. For an even deeper dive into naps and how to make the most of them with WHOOP, check out: Podcast No. 57: Naps–Your Greatest Recovery Amplifier

Take the guesswork out of your sleep

Understanding the general rules of napping is a great first step. To truly optimize your performance, you need personalized insights. WHOOP measures your daily sleep debt and strain to help you understand not just when to nap, but for how long.

It provides a complete picture of your sleep, so you can make smarter decisions to feel and perform your best.

Frequently asked questions about napping

What is the 30 90 rule for naps?

The 30/90 rule is a guideline for napping. It suggests you should either nap for less than 30 minutes to avoid deep sleep and grogginess, or for a full 90 minutes to complete an entire sleep cycle. This helps you wake up feeling either quickly refreshed or fully restored.

Is a 60-minute nap okay?

A 60-minute nap can be beneficial for improving memory, but it comes with a high risk of sleep inertia. During a nap of this length, you are likely to be in the deepest stage of sleep. Waking up from deep sleep often leaves you feeling groggy and disoriented for a while.

If you have time to overcome the grogginess, it can be restorative. However, for a quick boost, a shorter or longer nap is usually better.

How do I know if I need a nap?

Listen to your body. Signs that you might benefit from a nap include feeling drowsy, having trouble concentrating, making unusual mistakes, or feeling irritable. WHOOP can also help by showing you your daily Recovery score and sleep debt.

A low Recovery or high sleep debt is a strong indicator that your body could use the restorative power of a nap.