Body Mass Index (BMI) - how to calculate: formula and calculator

Body Mass Index (BMI) - how to calculate: formula and calculator

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The material was prepared by the site team with the support of our experts: athletes, trainers and nutrition specialists. Our team. .

During a physical examination or when losing weight, the height-to-weight ratio is often used using a body mass index (BMI) , BMI).

The technique was proposed by the Belgian scientist A. Quetelet in 1869, and is currently used by most doctors and nutritionists.

Body Mass Index (BMI) - how to calculate: formula and calculator

Quetelet formula

You can calculate the index without visiting a specialist . All you need to know is your own weight and height. The calculation procedure is as follows: divide the body weight by the height squared.

Example: calculate BMI for a person with a height of 170 cm and a weight of 90 kg.

BMI = 90 / (1.7²) = 31 (results are determined in kg / cm²)

For convenience, use a simple calculator:

* The BMI calculator gives an approximate estimate, is for reference only and does not replace a specialist’s consultation.

Deciphering the results

After calculating the body mass index, compare the obtained value with the data from the summary table:

  • Less than 16 - extremely low body weight.
  • 16-18.

    5 - insufficient body weight.

  • 18.5-25 - normal value.
  • 25-30 - non-critical excess of the norm.
  • 30-35 - overweight.

  • 35-40 - obesity.
  • More than 40 - obesity, dangerous to health.

We recommend adhering to normal BMI values, but if you are in the range of "25-30", do not panic. Slightly reduce your carbohydrate intake and drive more.

Advantages and disadvantages of the Quetelet formula

The main advantage of BMI is simplicity.

Anyone can calculate their own value and, without visiting a doctor, begin to take active steps to return body weight to normal levels.

The disadvantages of the method include its low accuracy. For example, if you calculate the body mass index of a professional athlete, the result is likely to be incorrect. This is explained by the fact that athletes have well-developed muscles, which will give overestimated values ​​of the index.

In addition, the Quetelet method does not take into account gender and age differences .

The BMI of a fifteen-year-old will be much lower than the average norm. The same applies to older people over 60.

It is recommended to use the BMI calculation methodology only as a guide. If an accurate assessment of your physical condition is necessary, consult your doctor.

Other methods

The Quetelet index is not the only one.

Many formulas have been developed that suggest determining the “ideal” body weight for a particular person. Consider the popular ones:

  • Brightman's formula: Nm = (height * 0.7) - 50.
  • Noorden's formula: Nm = (height * 420) / 1000.
  • Bernhard's formula: Nm = (height * chest volume) / 240.

  • Oder formula: Nm = (distance from the toe to the pubis * 2) - 100.

Nm - normal body weight; All growth values, as well as volumes and distances should be taken in centimeters.

In addition to the Quetelet index, specialists use a method for determining the percentage of fat with a caliper. These are medical ticks designed to measure the thickness of skin folds in different parts of the body.


If your BMI is outside the normal range, use simple but effective tips:

  • Review your diet .

    We are not talking about a strict diet, but about reducing calories. It’s best to reduce your calorie intake by avoiding fast carbohydrates - sugar, confectionery. Replace them with fruit. Refuse fast food, smoked meats and snacks. Recommended ratio BZHU for weight loss: 50/20/30.

  • Play sports . If you have never been involved in physical activity, do not immediately run a marathon. Especially if you are overweight or obese. Start with evening walks at a calm pace. When you feel that it has become easy for you to walk, increase the pace.

    By the way, walking the Scandinavian style is considered an excellent training option for beginners. Walk at least 40 minutes a day. And only after 2-3 months of regular walks can you gradually switch to jogging.

  • Take up strength training . Sign up for the gym.

    We recommend conducting fitness training under the supervision of an experienced trainer. This is necessary to monitor your condition and prevent dangerous loads.

  • Avoid stressful situations . Many tend to "seize" strong feelings and stress. This is due to the work of the autonomic nervous system and the desire to receive "hormones of joy" in a difficult environment.

    Try to avoid strong stresses, and if it does not work out, react to them correctly, for example, do breathing exercises instead of going to a fast-food cafe.

  • Give up bad habits . Beer is a high-calorie product. It is not for nothing that avid fans of a foamy drink have excess body weight. If you want to be healthy and beautiful, drink natural kvass.

    Cigarettes should also be phased out. Daily inhalation of cigarette smoke adversely affects the heart and blood vessels, which are already exposed to a lot of stress with excess weight.

Overweight can cause many dangerous diseases. Therefore, if you have extra pounds and at the same time you experience regular ailments, be sure to consult a doctor. Only a specialist can correctly assess your condition and make an accurate diagnosis.

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Body Mass Index (BMI) - how to calculate: formula and calculator

FitNavigator. ru / edition

The material was prepared by the site team with the support of our experts: athletes, trainers and nutrition specialists. Our team. .



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