You’ve probably heard that the heart is about the size of a fist. But have you ever wondered how much it actually weighs?
It’s not something most people think about—until they’re studying the body, watching a medical show, or just curious about how our organs work. So, let’s answer the big question:
The average human heart weighs between 250 to 350 grams (about 9 to 12 ounces).
That’s roughly the weight of a large apple or a small grapefruit.
But that number isn’t the same for everyone. The weight of the heart can change based on age, sex, body size, fitness level, and even health conditions.
In this article, we’ll break down everything you need to know about the weight of the human heart. We’ll cover:
- How much a man’s heart weighs vs. a woman’s
- How a child’s heart compares
- What makes the heart heavier or lighter
- Why heart weight matters for health
- And even some fun facts you’ve probably never heard
All explained in plain, simple English—no confusing medical jargon. Just clear, reliable facts from trusted health sources like the American Heart Association, Mayo Clinic, and the National Institutes of Health.
Let’s dive in.
How Much Does the Average Human Heart Weigh?
As we said, the average adult human heart weighs between 250 and 350 grams, or 9 to 12 ounces.
But let’s get more specific.
Average Heart Weight in Men
Men usually have larger bodies and more muscle mass than women, including in the heart.
- Average male heart weight: 280 to 340 grams (10 to 12 ounces)
- Some sources say up to 350 grams is still normal
The larger size helps the heart pump blood through a bigger body frame.
Average Heart Weight in Women
Women tend to have smaller hearts because their overall body size is often smaller.
- Average female heart weight: 230 to 280 grams (8 to 10 ounces)
- Still strong and efficient, just slightly smaller
Even though it’s smaller, a woman’s heart beats slightly faster on average to keep up with the body’s needs.
Is a Heavier Heart Always Better?
Not necessarily. A heavier heart isn’t always a healthier one.
- A heart that’s too heavy might be struggling—like in heart disease.
- A heart that’s too light could mean poor development or malnutrition.
The ideal weight depends on the person’s body size and overall health.
How Big Is the Human Heart?
Weight isn’t the only thing that matters—size does too.
Size of the Heart: How Big Is It?
- The human heart is about 5 inches (13 cm) long
- 3.5 inches (9 cm) wide
- 2.5 inches (6 cm) thick
To picture it: your heart is about the size of your clenched fist.
Kids are often taught to make a fist and say, “My heart is this big!” And it’s true—your heart matches the size of your hand pretty closely.
But remember: a bigger person usually has a bigger heart. So a tall adult’s heart will be larger than a child’s, even if both are healthy.
How Much Does a Child’s Heart Weigh?
Kids grow fast—and so does their heart.
A baby’s heart is tiny compared to an adult’s, but it works hard from day one.
Newborn Baby Heart Weight
- At birth: About 20 to 25 grams (less than an ounce)
- That’s about the weight of a golf ball
Even though it’s small, a newborn’s heart beats around 120 to 160 times per minute—much faster than an adult’s—to support rapid growth.
Child’s Heart Weight by Age
As a child grows, so does their heart:
- 1 year old: ~40 grams
- 5 years old: ~70 grams
- 10 years old: ~150 grams
- Teenager (15–17): ~200 to 250 grams
By late teens, the heart is close to adult size and weight.
This growth happens naturally as the body gets bigger and needs more blood pumped every second.
What Factors Affect the Weight of the Heart?
Not everyone’s heart weighs the same. Several things can make a heart heavier or lighter.
Let’s look at the main factors.
1. Age
- Babies: Very light hearts (20–25g)
- Adults: Heavier (250–350g)
- Older adults: May gain or lose heart weight based on health
With age, the heart muscle can thicken (especially if blood pressure is high), making it heavier.
2. Sex (Male vs. Female)
As mentioned:
- Men have heavier hearts (280–350g)
- Women have lighter hearts (230–280g)
This is normal and linked to body size and hormones.
3. Body Size and Height
Taller, larger people usually have bigger, heavier hearts because they need to pump blood farther.
Think of it like engine size in a car—a bigger vehicle needs a stronger engine.
4. Fitness Level and Exercise
Athletes often have heavier hearts—but in a good way.
- Athlete’s heart: A condition where the heart muscle thickens and chambers enlarge due to intense training.
- This is healthy and helps the heart pump more blood with each beat.
- Can add 50–100 grams to heart weight.
But it’s not dangerous—just a sign of a strong, well-trained heart.
5. Health Conditions
Some diseases can make the heart heavier or weaker.
Conditions That Increase Heart Weight:
- High blood pressure (hypertension): Makes the heart work harder, so the muscle thickens (called left ventricular hypertrophy).
- Heart valve disease: Leaky or narrow valves force the heart to pump harder.
- Cardiomyopathy: Disease of the heart muscle that causes it to enlarge or stiffen.
Conditions That May Reduce Heart Weight:
- Malnutrition or starvation: The body breaks down muscle, including heart tissue.
- Advanced heart failure: In some cases, the heart muscle can waste away.
So, heart weight can be a clue to overall health.
Why Does Heart Weight Matter?
You might think, “So what if my heart is a little heavier or lighter?” But doctors actually care about heart weight—for good reason.
1. Heart Weight and Heart Disease
A heart that’s too heavy can be a warning sign.
For example:
- If the left ventricle (the main pumping chamber) is too thick, it may not fill with blood properly.
- This can lead to heart failure, where the heart can’t pump enough blood.
Doctors use imaging tests like echocardiograms to measure heart size and muscle thickness.
2. Autopsy and Forensic Science
After death, pathologists weigh the heart during an autopsy.
- A heart weighing over 400 grams is often considered enlarged (cardiomegaly).
- This can help explain the cause of death—like heart attack, high blood pressure, or drug abuse.
3. Organ Transplants
When matching a donor heart to a recipient, size matters.
- A heart that’s too big or too small won’t fit or work well.
- Doctors consider height, weight, and heart size when making matches.
So yes—heart weight is more than just a fun fact. It’s a health clue.
How Is Heart Weight Measured?
You can’t step on a scale and weigh your heart—but doctors have ways to estimate or measure it.
1. Echocardiogram (Echo)
This is the most common way.
- Uses sound waves (ultrasound) to create pictures of the heart.
- Can measure the thickness of the heart walls and the size of the chambers.
- Estimates heart mass in grams.
It’s painless, quick, and done while you’re lying down.
2. MRI (Magnetic Resonance Imaging)
- Gives very detailed images of the heart.
- Most accurate for measuring heart weight and structure.
- Used when more detail is needed.
3. CT Scan
- Uses X-rays to create cross-sectional images.
- Can show heart size and calcium buildup.
- Less common for heart weight, but still useful.
4. Direct Weighing (After Death)
In autopsies, the heart is removed and weighed on a scale.
- This gives the exact weight.
- Helps determine if heart disease was present.
Can the Heart Change Weight Over Time?
Yes—your heart isn’t stuck at one weight for life.
It can get heavier or lighter depending on what’s happening in your body.
When the Heart Gets Heavier
- Exercise: Athletes’ hearts grow stronger and larger.
- High blood pressure: The heart muscle thickens to pump against higher pressure.
- Pregnancy: The heart works harder and may gain a little weight temporarily.
- Obesity: Extra body weight means the heart pumps more blood, which can increase its size.
When the Heart Gets Lighter
- Weight loss: If you lose a lot of weight, your heart may shrink slightly.
- Lack of exercise: A sedentary lifestyle can weaken the heart muscle.
- Malnutrition: Not getting enough protein or calories can cause heart muscle loss.
- Certain diseases: Like cancer or advanced heart failure.
So, your heart is dynamic—it changes with your lifestyle and health.
Fun Facts About the Human Heart
Now that we’ve covered the weight, let’s have some fun with cool heart facts.
1. Your Heart Beats About 100,000 Times a Day
That’s over 30 million times a year and 2.5 billion times in a lifetime.
Each beat pumps about ½ cup of blood—adding up to 2,000 gallons per day.
2. The Heart Can Keep Beating Outside the Body
Under the right conditions, a heart can continue beating even when removed—thanks to its own electrical system.
This is how heart transplants work.
3. The Heart Starts Beating 4 Weeks After Conception
Before the brain is fully formed, the heart begins to beat at just 22 days old in the womb.
It’s one of the first organs to function.
4. The Hardest-Working Muscle in the Body
Even though it’s not the strongest, the heart is the most endurance-trained muscle.
It never rests. Even when you sleep, it keeps pumping.
5. The Heart Has Its Own Electrical System
It doesn’t need the brain to beat. Special cells in the heart generate their own electrical signals.
That’s why a heart can beat on its own in a lab.
6. Your Heart Rate Changes with Emotions
- Love or excitement: Heart races
- Fear: Heart pounds
- Sadness: Heart may feel “heavy”
Emotions and the heart are deeply connected—both physically and emotionally.
What Is the Heaviest Human Heart Ever Recorded?
You might be wondering: just how heavy can a human heart get?
The heaviest recorded human heart weighed 2,860 grams—that’s over 6 pounds!
It belonged to a man with severe cardiomegaly (enlarged heart) due to long-term high blood pressure and heart disease.
Most hearts over 500 grams are considered dangerously enlarged.
For reference:
- Normal: 250–350g
- Enlarged: 400g+
- Severe: 500g–700g+
- Record-breaking: 2,860g
This shows how serious heart disease can become if left untreated.
What Is the Lightest Human Heart?
On the other end, the lightest hearts are found in newborns.
- Lowest recorded weight: Around 15–20 grams in premature babies.
- Some babies born with heart defects may have underdeveloped hearts.
With medical care, many of these babies grow strong hearts over time.
How Does the Heart Compare to Other Organs?
Let’s see how the heart stacks up against other major organs in weight.
| Heart | 250–350g |
| Brain | 1,300–1,400g |
| Liver | 1,400–1,600g |
| Lungs(both) | 1,000–1,300g |
| Kidneys(both) | 300–350g |
| Skin(total) | 8,000g (8kg) |
So while the heart isn’t the heaviest organ, it’s one of the most vital.
Without it, none of the others could function.
Can You Live With a Heavier or Lighter Heart?
Yes—many people live with hearts that are slightly heavier or lighter than average.
As long as the heart pumps blood effectively, small differences in weight are normal.
But if the weight change is due to disease, it can become dangerous over time.
The key is how well the heart works, not just how much it weighs.
How to Keep Your Heart Healthy and at a Normal Weight
The best way to keep your heart at a healthy weight is to live a heart-healthy lifestyle.
Here’s how:
1. Eat a Balanced Diet
- Focus on fruits, vegetables, whole grains, lean proteins, and healthy fats.
- Limit salt, sugar, and processed foods.
- Too much salt raises blood pressure, making the heart work harder.
2. Exercise Regularly
- Aim for 150 minutes of moderate exercise per week (like brisk walking).
- Strength training also helps heart health.
- Exercise keeps the heart strong but not overworked.
3. Control Blood Pressure
- High blood pressure is a top cause of heart thickening.
- Check your BP regularly.
- Ideal: less than 120/80 mm Hg
4. Avoid Smoking
- Smoking damages blood vessels and raises heart rate.
- Quitting reduces heart disease risk quickly.
5. Limit Alcohol
- Too much alcohol can weaken the heart muscle (alcoholic cardiomyopathy).
- Men: no more than 2 drinks/day
- Women: no more than 1 drink/day
6. Manage Stress
- Chronic stress raises blood pressure and heart rate.
- Try deep breathing, meditation, or yoga.
7. Get Regular Checkups
- See your doctor for routine heart screenings.
- An ECG or echocardiogram can catch problems early.
Does Heart Weight Affect How Long You Live?
Not directly—but what causes the weight change does.
- A slightly heavier heart from exercise? Great for longevity.
- A heavier heart from high blood pressure? Increases risk of heart failure and early death.
- A shrinking heart from malnutrition? Also dangerous.
So it’s not the number on the scale—it’s the reason behind it that matters.
People with healthy hearts, normal weight, and good habits tend to live longer, more active lives.
Can You Weigh Your Own Heart?
No—not while you’re alive.
There’s no home scale for your heart! But doctors can estimate its weight using:
- Echocardiogram
- MRI
- Body size and blood pressure readings
If you’re concerned about your heart health, talk to your doctor. They can check how well it’s working—even if they can’t put it on a scale.
How Do Animals’ Hearts Compare?
Just for fun, let’s compare the human heart to animals.
| Blue whale | ~400 kg (880 lbs) | Largest heart in the animal kingdom |
| Elephant | ~12–21 kg (26–46 lbs) | Very large, but beats slowly |
| Dog | 300–500g | Similar to human, depends on breed |
| Cat | 20–30g | Tiny, but beats very fast |
| Hummingbird | 0.1g | Smallest known heart |
Fun fact: A hummingbird’s heart beats 1,200 times per minute!
So while our heart isn’t the biggest or fastest, it’s perfectly designed for human life.
Final Answer: What Is the Weight of the Human Heart?
To wrap it all up:
✅ The average human heart weighs 250 to 350 grams (9 to 12 ounces).
✅ Men’s hearts are usually heavier (280–350g) than women’s (230–280g).
✅ A newborn’s heart weighs just 20–25g and grows with the child.
✅ Factors like age, fitness, body size, and health affect heart weight.
✅ A heart that’s too heavy or too light can signal health problems.
✅ You can’t weigh your heart at home, but doctors can estimate it with tests.
Your heart may not be the biggest organ, but it’s one of the most important. It works nonstop, pumps thousands of gallons of blood, and keeps every part of your body alive.
So treat it well. Eat right, stay active, and listen to it—literally and figuratively.
Because when your heart is healthy, your whole life feels better.
Frequently Asked Questions (FAQ) on What Is the Weight of the Human Heart?
Q: What is the average weight of a human heart in pounds?
About 0.6 to 0.8 pounds (since 350 grams = 0.77 lbs).
Q: How much does a woman’s heart weigh?
On average, 230 to 280 grams (8 to 10 ounces).
Q: How much does a man’s heart weigh?
Typically 280 to 350 grams (10 to 12 ounces).
Q: Does heart weight increase with age?
It can—especially if you have high blood pressure or heart disease. But in healthy aging, changes are small.
Q: Can exercise increase heart weight?
Yes—athletes often have heavier, stronger hearts due to training. This is normal and healthy.
Q: What is the size of the human heart?
About 5 inches long, 3.5 inches wide, and 2.5 inches thick—roughly the size of a fist.
Q: How much does a baby’s heart weigh at birth?
Around 20 to 25 grams (less than an ounce).
Q: Can a heavy heart be dangerous?
Yes—if it’s due to disease like high blood pressure or cardiomyopathy. But athlete’s heart is safe.
Q: What causes an enlarged heart?
High blood pressure, heart valve disease, heart attack, obesity, and genetic conditions.
Q: How do doctors measure heart weight?
Using echocardiograms, MRI, or CT scans. After death, it’s weighed directly during autopsy.
Q: Is a bigger heart stronger?
Not always. A moderately larger heart from fitness is strong. But an enlarged heart from disease is weak and strained.
Q: Can heart weight be reduced?
Yes—by treating high blood pressure, losing weight, or managing heart disease.
Q: What is the heaviest heart ever recorded?
2,860 grams (over 6 pounds)—due to severe heart disease.
Q: Does heart weight affect heart rate?
Not directly. Heart rate is more affected by fitness, age, and emotions.
Q: Can a person live with a weak or small heart?
Yes, with treatment. Medications, devices (like pacemakers), or transplants can help.
Q: Are heart size and hand size related?
Yes—your heart is usually about the size of your clenched fist. This is a handy (pun intended) way to estimate heart size.
Q: Does obesity increase heart weight?
Yes—extra body weight makes the heart work harder, which can cause it to grow larger over time.
Q: Can stress make your heart heavier?
Not directly, but chronic stress raises blood pressure, which can lead to heart muscle thickening.
Final Thoughts
The human heart may only weigh about a pound, but it carries the weight of your entire life.
It doesn’t ask for much—just healthy food, movement, and care. In return, it beats over 100,000 times a day without stopping.
Now you know: the average weight of the human heart is 250 to 350 grams, and it changes based on who you are and how you live.
So take care of it. Your heart is worth its weight in gold—literally and figuratively.
