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BMI Calculator

Being healthy must be the top priority of all human beings. A healthy life guarantees a life without chronic diseases and increased life expectancy. Now, one way to ensure a healthy life is to maintain normal body weight. But what is the normal body weight? How can you know that a certain weight is normal for you? You may feel okay but you can be seriously underweight. That is why Body Mass Index (BMI) is created to tell you if you are underweight, overweight, or have a perfectly normal body weight.

How can you calculate your BMI?

You can calculate BMI with the help of two formulae. In the first formula, you can calculate your BMI by taking your weight in kilograms and dividing it by your height taken in meters.

BMI (kg/m2) = mass (kg) / height 2(m)

In the second formula, you can calculate your BMI by taking your weight in pounds and dividing it by your square of height in inches times 703.

BMI (kg/m2) = mass (lb) / height 2(in) × 703

How can our BMI calculator help you?

If you're not a mathematics person, the formula for calculating BMI might scare you. As for the others, it can be plain time-consuming. Justfreetools.com has designed a BMI calculator to provide you with the easiest way of calculating your BMI.

It is an efficient tool that will assist you in calculating your BMI in the quickest way possible. No matter where you are or what you're doing, if you have good internet access, you can use our tool efficiently. Of course, we know how precious your time is, that is why we have developed such a tool that will give your results in a matter of a few seconds. You'll get your score in a blink of an eye! But how can you use this tool?

How can you use our BMI calculator?

Our BMI calculator tool is extremely easy to use. All you have to do is follow the steps mentioned below and you'll be good to go.

• When you open our BMI calculator tool, you will see two options in which you can calculate your BMI US/UK Units or Metric Units (In the US/UK units, your body weight will be calculated in terms of pounds, whereas in metric units, your body weight will be counted as kilograms)
• Select the unit according to your preferences and then fill out the necessary boxes.
• Once you're done adding your height and weight, click on "calculate".
• Your BMI along with your BMI category and health risk will pop up on your screen.

If you want to give it another go, select "reset" and repeat the mentioned above steps. You may have noticed that we used the term "BMI category" in the last step. Refer to the next section to know about the BMI category.

BMI category table

The BMI category table tells you whether you are underweight, overweight, or have normal body weight in terms of the BMI range. It also tells you the health risk associated with being underweight and overweight. The BMI category table is mentioned below.

BMI Category	BMI Range (kg/m2)	Health risk
Underweight	18.4 and below	Malnutrition risk
Normal weight	18.5 - 24.9	Low risk
Overweight	25 - 29.9	Enchanced risk
Moderately obese	30 - 34.9	Medium risk
Severely obese	35 - 39.9	High risk
Very severely obese	40 and above	Very high risk

Benefits of a BMI Calculator

Using a BMI calculator proves to be a lot more beneficial than you can imagine. Some of the most prominent benefits of a BMI calculator are shown below:

• It helps in acquiring the accurate BMI

When you're calculating your BMI, there are chances that you can make slight mistakes. Let's give it to human error. Now, BMI has a direct influence on your health and you can't take care of your health properly if your BMI isn't correct. That is why it is quite important that you get your BMI right.

What other way can you get the most accurate BMI than a tool that is meant to do this?

Our BMI calculator provides the most accurate results to our users in no time. So, instead of scribbling down formulae and converting weights and heights, use our BMI calculator and get your results instantly.

• It helps in guiding your fitness and health goals

If you want to set your health and fitness goals, it may come in handy if you know your BMI beforehand. For instance, if your BMI is 34, you will know that you're overweight. You will then consume a healthy diet and exercise regularly to shed those extra pounds. On the other hand, if your BMI is 15, it means that you're at malnutrition risk and the best way to be healthy is to eat nutritious food items and take about 3,500 calories per day.

• It is objective and tells you the truth

How many times has your best friend told you that you look healthy and beautiful? How many times have you stood up in front of the mirror thinking that you're healthy? Where words and eyes may lie, your BMI won't. It will always offer you the truth. You may fool yourself with the delusion that you look fine but your BMI will tell you if you're of healthy weight or not. Using our BMI calculator will help you know your exact BMI and then you can proceed with your fitness goals accordingly. With the help of this calculator, you can actually make yourself healthy.

FAQs (Frequently Asked Questions)

Are there any other ways to assess excess body fatness other than a BMI calculator?

There are some other methods that you can use to calculate your BMI. These are:

• Skinfold thickness measurements (with calipers)
• Underwater weighing
• Bioelectrical impedance
• Dual-energy x-ray absorptiometry (DXA)
• Isotope dilution

However, all these methods are quite expensive and they are not readily available. In addition to this, you can't perform these methods on your own, you will need trained personnel to use them. In such circumstances, it is better if you go with a simple BMI calculator to tell you about your health.

How can you interpret BMI for adults?

The body mass index of the adults can be interpreted using the BMI category table mentioned above. This table can be used to interpret BMI for men and women of all ages and body types. Consider a male is about 5'9'' then the weight range, BMI range, and health status are:

Height	Weight Range	BMI	Weight Status
5′ 9″	124 lbs or less	Below 18.5	Underweight
	125 lbs to 168 lbs	18.5 to 24.9	Healthy Weight
	169 lbs to 202 lbs	25.0 to 29.9	Overweight
	203 lbs or more	30 or higher	Obesity

Can you interpret BMI for children and teenagers in the same way as adults?

For children and teenagers, BMI is interpreted quite differently than that of adults. However, the formula used for calculating BMI for children and teenagers is the same as that for adult BMI. The BMI of teenagers and children depends on age and sex due to the fact that the body fat amount of a child or a teenager tends to change with age. Also, there is also a difference in the amount of body fat between boys and girls. These differences are taken into account by the CDC (Centers for Disease Control and Prevention) BMI-for-age growth charts and the BMI for boys and girls are shown as a percentile ranking.

Category	Percentile Range
Underweight	<5%
Healthy weight	5% - 85%
At risk of overweight	85% - 95%
Overweight	>95%

The percentile ranking was obtained by using the data of 2- to 19-year-olds from the population of the United States from 1963-65 to 1988-94.

At or above the 95th percentile, the children between the ages of 2 to 19 were termed obese from 1963 to 1994. For instance, if there is a 10 years old boy with a weight of 102 pounds and an average height of 56 inches, the BMI of that boy will be 22.9 kg/m2. With this BMI, the boy would reside in the 95th percentile which means that the weight of the boy is greater than 95% of the similarly aged boys. In this way, the boy will be termed obese.

How good is BMI as an indicator of body fatness?

Scientists have found a strong association between body fatness and the BMI of a person. However, keep in mind that even if the two individuals have the same BMI, there may be a difference in their body fatness level.

There can be several reasons for that:

• Women generally have more body fat than men at the same BMI.
• The ethnic/racial group may also have a role in the difference in body fat at the same BMI.
• Older adults generally have more body fat than younger adults at the same BMI.
• Non-athletes tend to have more body fat than athletes with the same BMI.

However, the accuracy of BMI may tend to be more in people with high body fatness and levels of BMI. If a person has a high BMI, let's say 35 kg/m2, it means that the person either has high levels of body fat or high lean body mass which includes the weight of bones and muscle. Once you know your BMI, you can consult a healthcare professional to evaluate the associated health risks with your health status.  

If an athlete or any other person with a lot of muscle has a BMI over 25, is that person termed overweight or obese?

According to the BMI category table mentioned above, any person who has a BMI over 25 is termed overweight. However, if we're talking about athletes they may not be considered overweight because athletes have increased muscularity instead of a high amount of body fat.

What are the health consequences of obesity for adults?

Obese people are a risk for a large number of chronic health conditions and diseases that include:

• Mortality (all causes of death)
• High levels of triglycerides (dyslipidemia), high LDL cholesterol, or low HDL cholesterol
• Coronary heart disease
• Gallbladder disease
• Breathing problems and sleep apnea
• A variety of cancers (breast, kidney, liver, endometrial, colon, and gallbladder)
• Mental health problems such as anxiety, depression, etc.
• Hypertension (high blood pressure)
• Type II Diabetes
• Stroke
• Osteoarthritis (within a joint, the cartilage and bone start to break)
• Increased oxidative stress and chronic inflammation  
• Low life quality
• Difficulty with physical functioning and lots of body pain

What are the health consequences of being underweight?

Where obesity can have detrimental health consequences, there are also several risks associated with being underweight.

• Malnutrition and vitamin deficiencies
• Anemia (lowered ability to carry blood vessels)
• A decrease in the functioning of the immune system
• Reproductive issues in women because of hormonal imbalances
• In underweight women, there is a high risk of miscarriage in the first trimester
• Increased risk of mortality
• Osteoporosis (a disease that can break your bones or cause weakness of the bones)
• Issues in growth and development, especially in teens and children
• Increased complications after a surgery

There are also some cases where being underweight can have a strong association with some underlying conditions such as anorexia nervosa. It is vital to treat such diseases by consulting a doctor immediately to avoid any of the mentioned above diseases.

What are the trends of BMI for adults in the US?

Since the 1970s, the number of obese people has considerably increased in the United States. However, lately, the BMI trends have leveled off except for older adults, especially women. In women 60 years of age or older, there is still a high health risk because of obesity.  

Conclusion

That's it, folks! Having knowledge about your BMI is quite important because that is how you'll know whether you need to consult a healthcare professional or not. Use our BMI calculator right now and find what BMI category you reside in! You never know, this might be the right time to consume a healthy diet.