What Is a Normal Sleeping Heart Rate? Ranges, Changes During Sleep & When to Worry

If you wear a smartwatch, fitness tracker or smart ring, you may wake up to a heart-rate number from the night before that looks different than others you’ve seen. The obvious question is: Is that number normal?

Your heart rate naturally changes while you sleep, and it will often be lower than it is while you're awake. It can also rise and fall throughout the night as you go through different stages of sleep, dream, move around or wake up.

Your age, fitness level, medications, overall health and usual baseline can all affect what's normal for you, as there is no true universal normal. This article explains what a normal sleeping heart rate generally looks like, why it changes throughout the night and when an unusual reading may be worth discussing with a healthcare provider.

What Is a Normal Heart Rate While Sleeping? 

For many healthy adults, a typical sleeping heart rate is around 50 to 75 beats per minute (BPM), although lower readings, including those in the 40s, can also be normal. There is no single number or range that applies to everyone, and a reading outside these examples does not automatically mean something is wrong.

Your heart rate measures how many times your heart beats each minute. While the normal waking resting heart rate for most adults is generally 60 to 100 BPM, heart rate slows during sleep as your body moves through different stages of rest.

Since there are several factors that can change an individual's baseline, one unusual number is often less informative than a consistent pattern over time, especially when considered alongside any symptoms.

 Normal Sleeping Heart Rate by Age 

Heart rate changes with age, especially from childhood into adulthood.

• Infants and young children: Heart rates during sleep are normally higher than adult rates and vary considerably with age.
• Older children and teenagers: Heart rate gradually slows as they grow and moves closer to adult patterns.
• Adults: Approximately 40–60 BPM is one commonly cited sleeping range, although individual readings vary.
• Older adults: Adult ranges still provide general context, but medications, fitness and medical conditions are especially relevant.

For adults, your usual nighttime pattern is often more useful than comparing yourself with a rigid age chart. A noticeable change from what is normal for you may matter more than being a few beats above or below someone else’s average.

Sleeping Heart Rate vs. Resting Heart Rate 

Sleeping heart rate and resting heart rate sound similar, but they measure your heart rate at different times:

• Resting heart rate is your heart rate while you're awake, calm and physically inactive.
• Sleeping heart rate is your heart rate while you're actually asleep.

Your sleeping heart rate is often lower because your body is in a more restful state and your heart doesn't need to work as hard. Wearable devices can make the comparison a little confusing because they don't all calculate these numbers in the same way. Some may show an overnight average, a lowest heart rate or a separate resting heart-rate measurement.

It’s important that when you’re comparing readings, make sure you're looking at the same type of measurement rather than assuming two different numbers should match.

Why Your Heart Rate Changes Throughout the Night

Your body moves through different stages of sleep several times during the night, and your heart responds along with it. During deeper non-REM sleep, heart rate and blood pressure generally decrease. During REM sleep, when vivid dreaming is more common, heart rate can become more variable and may temporarily increase. Heart rate also rises as you wake up.

You may also see temporary changes related to:

• Rolling over or changing position
• Briefly waking up
• Getting out of bed

If you look at an overnight heart-rate graph, some peaks and valleys are normal. What matters most is whether the changes are very different from your normal pattern, happen repeatedly or occur along with symptoms.

What Can Affect Your Sleeping Heart Rate?

Your sleeping heart rate can be influenced by several things, and some factors may push it higher while others may make it lower.

Factors That May Cause A Higher Sleeping Heart Rate 

Reasons your sleeping heart rate can increase  include:

• Illness or fever
• Stress or poor-quality sleep
• Alcohol
• Caffeine or other stimulants
• Certain medications
• Sleep disorders such as sleep apnea
• Abnormal heart rhythms

If your sleeping heart rate stays unusually high, repeatedly spikes or is significantly different from your normal pattern, it may be worth discussing with a healthcare provider, especially if you're experiencing these changes alongside other concerning symptoms like dizziness, weakness or shortness of breath.

For a deeper look at elevated nighttime readings, see High Heart Rate While Sleeping: Causes, Sudden Spikes and When to Worry.

Factors That May Cause A Lower Sleeping Heart Rate 

A lower sleeping heart rate can sometimes be completely normal, especially if you are physically active. However, other factors that may lower heart rate include:

• Certain medications
• Your normal individual baseline
• Some heart-rhythm conditions

A low sleeping heart rate may deserve more attention if it’s new for you or occurs with symptoms such as:

• Dizziness
• Fainting or near-fainting
• Unusual weakness
• Shortness of breath
• Chest discomfort

A healthcare provider can help determine whether your sleeping heart rate is normal for you or requires further evaluation.

Heart Rate Readings From Smartwatches and Sleep Trackers

Smartwatches, fitness trackers and smart rings can be helpful because they allow you to see patterns that would otherwise be difficult to notice while you're asleep.

Most consumer wearables use optical sensors and software to estimate your heart rate. Research suggests that some devices can measure nighttime heart rate reasonably well, but accuracy varies between devices and conditions. They aren't interchangeable with an electrocardiogram (ECG) or other medical heart monitoring.

An unusual reading on one of these devices can also be affected by things such as:

• Movement
• How the device fits
• Poor skin contact
• Sensor position
• Differences in the device's software

If unusual readings continue appearing over several nights, save the data or screenshots to show your healthcare provider. The pattern may provide useful context if further evaluation is needed.

Heart Rate vs. HRV

Many wearables also show heart rate variability, or HRV. Heart rate tells you how many times your heart beats in one minute, whereas HRV measures small differences in the amount of time between individual heartbeats.

They're related measurements, but they don't mean the same thing. Just like heart rate, there also isn't one universal HRV number that is “good” for everyone. If you track HRV, your own pattern over time is generally more useful than comparing your number directly with a chart.

When to See a Doctor in Queens or Brooklyn About Your Sleeping Heart Rate

It’s worth speaking with a healthcare provider when your sleeping heart rate is consistently outside your usual range, changes suddenly without a clear reason or occurs alongside other symptoms.

Signs that may deserve evaluation include:

• Repeated unexplained high or low readings
• A significant change from your usual nighttime pattern
• Frequent or dramatic heart-rate spikes
• Irregular rhythm notifications from your wearable
• Racing or pounding sensations at night
• Dizziness or fainting
• Shortness of breath
• Known heart disease or a history of abnormal heart rhythms
• Loud snoring, gasping or other signs of possible sleep apnea

The type of evaluation will depend on what you're experiencing. A cardiology evaluation may be appropriate when there are concerns about heart rhythm or other cardiovascular causes. Sleep medicine evaluation may be useful when nighttime heart-rate changes occur alongside snoring, gasping, disrupted sleep or other signs of a sleep disorder.

At Advanced Medical Care, our cardiology and sleep medicine teams help patients throughout Queens and Brooklyn understand whether changes in nighttime heart rate may be related to heart health, sleep quality or both.

Advanced Medical Care provides care in Forest Hills, Queens and Brighton Beach, Brooklyn. If you've noticed a recurring change in your sleeping heart rate and aren't sure what it means, we can help you understand the pattern and whether further evaluation makes sense. Please call us at 347-571-9389 (Queens) or 929-552-2973 (Brooklyn) to schedule an appointment, or book online to get started. 

Remember, call 911 or seek emergency medical care if an abnormal heart rate occurs with severe or new chest pain, major difficulty breathing, fainting, signs of a stroke or other symptoms that feel serious.

Frequently Asked Questions About Sleeping Heart Rate

What is a good sleeping heart rate?

There isn't one perfect sleeping heart rate for everyone. Heart rate commonly slows below your daytime resting rate during sleep, and readings below 60 BPM can be normal, particularly in healthy or physically active adults. Your usual baseline, overall health and symptoms all help provide context.

Is your heart rate supposed to go down when you sleep?

Generally, yes. During non-REM sleep, your heart rate and blood pressure usually fall as the body moves into a more restful state. Heart rate may temporarily increase again during REM sleep, brief awakenings or waking in the morning.

Is sleeping heart rate lower than resting heart rate?

It often is. Resting heart rate usually refers to your heart rate while you're awake but calm and inactive, while sleeping heart rate is measured while you're asleep. Because the heart generally doesn't work as hard during restful sleep, sleeping heart rate may be lower.

Is a heart rate of 50 normal while sleeping?

A sleeping heart rate around 50 BPM can be normal for some adults, particularly people who are physically active or whose heart rate normally runs lower. A number becomes more important if it's new for you, unusually low compared with your normal pattern or accompanied by symptoms such as dizziness, fainting, shortness of breath or weakness.

Why does my heart rate spike while I'm asleep?

Short increases can happen during REM sleep, dreams, movement or brief awakenings. Repeated or unusually large spikes can have other causes and may deserve evaluation.

 Why is my sleeping heart rate higher than usual?

Several factors can raise your sleeping heart rate, including illness, poor sleep, stress, alcohol, stimulants, certain medications and sleep apnea. If the change continues or is significantly different from your usual pattern, it may be worth discussing with a healthcare provider.

Does sleeping heart rate change with age?

Yes, especially across infancy and childhood as heart rates gradually move toward adult patterns. Among adults, fitness level, medications, health conditions and your individual baseline may be more useful than relying on a rigid age-by-age chart.

Can a smartwatch accurately measure sleeping heart rate?

Wearables can be useful for tracking trends, and some devices perform well when measuring nighttime heart rate. However, accuracy varies between devices and individual readings can be affected by movement, fit, skin contact and device algorithms. A smartwatch shouldn't be treated as a replacement for medical heart monitoring.