BMI Calculator  
 

Is Body Mass Index Reliable? 

Children 

One of the main areas where BMI calculators struggle is when it comes to children.

Body mass index cannot always be taken as a reliable indicator of health in children because of the fact that each child is so different and constantly changing, so keep this in mind if you plan on using our BMI calculator for a child.  

Pregnant Women 

Another group that body mass index does not work well for is pregnant women.  

Pregnant women often weigh much more than average because of the increased fat stores they need for a child as well as the weight of the child itself, so this can make almost any BMI reading worthless if you are pregnant.  

There are specified “BMI calculator female” calculators out there that can take pregnancy into consideration, but even these calculators are not going to give you an accurate result.  

If You Are Very Muscular 

If you are very muscular, this can drastically skew the results of any BMI reading you get. 

Muscle mass is denser that fat, and if you have a lot of muscle, you could easily be classified as overweight or obese even when you are completely healthy. 

Once again, if you do a search for BMI calculator male there will be calculators that factor this in, but it’s important to know that BMI is just not a good measure of overall health for people who are muscular.  

 If You Are of Asian Origin 

It is a well-documented fact that body mass index is not a reliable index of health for people of Asian origin.

Asian people can generally be a little thinner or larger than other demographics while still being healthy, so a BMI may not necessarily be able to give people of Asian origin an accurate reading of their health. 

Older People (Over 65, Possibly Over 60) 

Another factor that may make BMI an unreliable predictor of health is age.  

A BMI calculator by age is only going to be somewhat accurate up until 60/65. 

After this, a strange phenomenon takes place with being overweight can actually be slightly beneficial for overall health.  

So, if you are over 60 and what to find out if your current bodyweight is healthy, it would be a good idea to see a GP.   

Alternative Estimates Of Weight-related Health Risks 

Waist Circumference 

This method measures the circumference of the waist at the narrowest point between the lower ribs and the iliac crest (the top of the hip bone).

It is used as an indicator of abdominal fat, which is associated with an increased risk of health problems such as type 2 diabetes, heart disease, and high blood pressure. 

Waist To Hip Ratio 

This method compares the circumference of the waist to that of the hips.  

It is used as an indicator of body fat distribution, with higher ratios indicating more abdominal fat. 

Like waist circumference, a higher waist-to-hip ratio is associated with an increased risk of health problems. 

Waist To Height Ratio 

This method compares the circumference of the waist to the person’s height. 

 It is used as an indicator of overall body fatness and is considered a better predictor of health risks than BMI (Body Mass Index) for some populations.  

A ratio of less than 0.5 is considered healthy, while a ratio of 0.5 or more is associated with an increased risk of health problems such as heart disease, diabetes, and high blood pressure. 
 

Calculating Your BMI 

Our BMI calculator uses a simple formula to determine your BMI based on your height and weight.  

Calculating your BMI online is never going to be completely accurate, and there are various factors that skew the results. 

However, it can give you a quick idea of what your BMI is in general. 

Limitations Of The BMI 

Not accurate for athletes and bodybuilders: BMI does not differentiate between muscle and fat, and hence it may not be accurate for athletes, bodybuilders, or people with high muscle mass, who may have a higher BMI but a lower body fat percentage. 

Doesn’t account for body shape: BMI also does not account for body shape or distribution of fat.  

People with a large waist circumference or excess abdominal fat, which is linked to an increased risk of heart disease and other health problems, may have a BMI within the healthy range but still have a higher risk of health problems. 

Doesn’t consider age and gender: BMI also does not consider age and gender. 

 For example, older adults tend to have more body fat than younger adults with the same BMI, and women tend to have more body fat than men with the same BMI. 

Doesn’t account for ethnicity: BMI may not be equally valid for all ethnic groups. 

some studies suggest that people of South Asian and African descent may have a higher risk of health problems at a lower BMI than people of European descent. 

Not suitable for pregnant women and children: BMI is not suitable for pregnant women and children, as their body composition changes during growth and development. 

BMI Weight Ranges 

Underweight 

A BMI (Body Mass Index) below 18.5 is considered underweight. 

Being underweight may indicate malnutrition, an eating disorder, or other health problems, and is associated with an increased risk of health problems such as weakened immune function, anemia, and osteoporosis. 

Healthy Weight 

A BMI between 18.5 and 24.9 is considered a healthy weight. 

People within this range have a lower risk of health problems associated with excess body weight, such as type 2 diabetes, heart disease, and certain types of cancer. 

Overweight 

A BMI between 25 and 29.9 is considered overweight.  

Being overweight is associated with an increased risk of health problems such as type 2 diabetes, heart disease, high blood pressure, and certain types of cancer. 

Obese 

A BMI of 30 or higher is considered obese.  

Being obese is associated with an increased risk of serious health problems such as heart disease, type 2 diabetes, stroke, and certain types of cancer. 

Waist To Height Ratio 

The waist-to-height ratio (WHtR) is not a BMI weight range but is another measure of body fatness.  

This ratio compares the circumference of the waist to the person’s height and is considered a better predictor of health risks than BMI for some populations.  

A ratio of less than 0.5 is considered healthy, while a ratio of 0.5 or more is associated with an increased risk of health problems such as heart disease, diabetes, and high blood pressure. 

What Your BMI Result Means 

Your BMI can give you an indication of how healthy or unhealthy your current body composition may be.  

If you are underweight, overweight, or even obese, then this could mean that you are at a higher risk of developing a range of various health conditions.  

You should try to make changes to your diet and exercise routine if you do fall into any of the aforementioned categories. 

However, a BMI calculator is not always correct. If you are very muscular or fall under any of the other exemptions we listed in this article, then you should not use BMI as a indicator of health.  

Healthy Eating 

Healthy eating is vital for maintaining a healthy BMI.  

By eating close to your maintenance calories (or higher or lower depending on your current body composition), eating a variety of foods, and eating a balanced diet, you will be much healthier as a whole and reduce your chances of many physical ailments.  

Healthy Weight For Adults 

The healthy weight for adults varies drastically depending on age, gender, and height.  

Losing Weight Safely 

Portion Sizes  

One of the best ways to lose weight safely is to just decrease your portion sizes. 

This method is extremely easy to implement and can lead to great results in the long run. 

It also happens to a good strategy for those who struggle to stick to diets.  

Vitamins And Minerals  

When trying to lose weight, it is essential that you still eat a balanced diet and get a ton of vitamins and minerals.  

If you think you may be deficit in some minerals or vitamins while dieting, supplementing a vitamin/mineral supplement can be incredibly effective.  

Benefits Of Exercise 

Another way you can lose weight safely is by exercising more often.  

There are a ton of benefits to exercise, from weight loss to preventing certain diseases and ailments.  

Moreover, you do not even have to exercise all that much to get its benefits – even just a brisk walk around town will do.  

Fad Diets Explained 

For one reason or another, most people turn to fad diets when trying to lose weight. 

This is a mistake. 

The only way to lose weight is by burning off or eating fewer calories than you need to maintain your current weight. 

This means that everything else is just fluff that is just going to make the whole process more difficult than it needs to be.  

Just stick to the basics.  

Obesity In Adults 

Obesity in adults is incredibly common.  

In fact, over 68.6% of men and 59.0% of women are obese according to a study in 2022. 

However, just because obesity is the norm does not mean we should accept it.  

Obesity is a serious issue that can increase the likelihood of a range of different health problems, and it is not just a personality trait or quirk as some people suggest. 

That’s not to say you should be disappointed in yourself or unhappy if you are obese – as long as you are taking steps to improve your health, you are doing great.  

BMI Calculator – FAQs 

What Is The Best BMI For Age? 

The BMI for your age will vary on other factors like height and weight.  

How Do I Calculate My BMI? 

You can calculate your BMI by using a BMI calculator.  

There are also other methods that involve measuring various parts of your body and putting the information through a somewhat complex formula.  

Is 14 Stone Overweight? 

No, 14 stone isn’t overweight if you are a muscular man or over 6 foot.  

However, for anyone who doesn’t fit the aforementioned categories, then 14 stone could be considered overweight.   

 
What Is The BMI For A 5 4 Woman? 

The BMI for a 5’4 woman will vary depending on build and weight. 

To get an accurate reading of someone’s BMI, knowing both height and weight is essential.  

What’s The Best BMI calculator UK? 

The best BMI calculator UK is the BMI calculator by MovingForwards.  

Is There a BMI Calculator NHS? 

Yes, there is a BMI calculator NHS. 

What is The Best BMI Calculator KG With Age? 

The best BMI calculator KG with age is the MovingForwards calculator. 

This calculator is simple to use and as accurate you can get with an online BMI calculator. 

What is the Best BMI Calculator KG? 

The best BMI calculator KG is the calculator by MovingForwards. 

This BMI calculator is easy to use and is available for both metric and standard measurement systems.  

 
Can you Sort a BMI Calculator by Age and Gender? 

Yes, you can sort a BMI calculator by age and gender.  

However, most BMI calculators do not feature these factors are there are just too many variables at play.