It is known that anthropometry is a scientific study of the measurements and proportions of the human body and organism through basic methodological methods. Some of the essential elements and forms of anthropometry used in practice are weight and height. The majority of the world’s population struggles with being overweight, which leads to obesity, many in one way or another decide on a healthy diet to improve effective weight loss. For this reason, we present you with a tool called an adjusted body weight calculator. It can help you save time to calculate your needs. How this calculation is performed and with the help of which formula you can find out below.

What is adjusted body weight?

Before we explain the calculation procedure using this calculator, we will explain the purpose of adjusted body weight. It is the name for the measure most commonly used to calculate the nutritional needs of certain people. If people with less metabolically active tissue use actual body weight to figure energy needs, this can overestimate the natural state and healthy BMI. The equation used in that case is based on the assumption that in most cases for obese people, 25% of excess weight is metabolically active tissue. For this reason, the use of a measure of adjusted body weight, better known by the abbreviation AjBW, is recommended.

How to calculate adjusted body weight?

You do not need to worry about the calculation because our calculator will help you with that and in a very fast and efficient way. In the continuation of the article, we will also explain the principle on which our calculator works, and now we will show you how you can calculate your adjusted bodyweight yourself. You need to have data on your ideal body weight (IBW) and actual body weight (ABW).

IBW means the amount of target weight at which all necessary nutritional requirements are met. It is calculated by taking into account body weight and BMI target values. The ideal body weight for men is 52 kg + 1.9 kg for every inch above 5 feet, while for the female part of the population, it is 49kg + 1.7kg for every inch above 5 feet. On the other hand, ABW is used to measure the actual value of the bodyweight of the subjects, which is best measured in the morning after urination. If ABW is measured correctly, you can later use it to calculate body mass index and other weight-related measures. When we consider the above terms, we calculate the adjusted body weight by adding the difference ABW and IBW multiplied by 0.4 to the ideal body weight.

Adjusted body weight formula

As for the calculation formula, it is straightforward to use. The factor of 0.4 or 40% is used to ensure an adjusted body weight in the case of persons who have more than 20% of their ideal body weight:

AjBW = IBW + 0.4 \cdot (ABW - IBW)

Where are:

  • AjBW – adjusted body weight
  • IBW – ideal body weight
  • ABW – actual body weight

How to use the adjusted body weight calculator?

Below are the steps you need to take to use our custom weight calculator properly. Just follow these instructions:

You need to enter data in the calculator about your gender, height, and your actual body weight value. The calculator will then further use all the data entered to determine your ideal body weight (IBW) needed to calculate the adjusted body weight. It should also be noted that there are different formulas for calculating the perfect weight, which are also accepted in practice for use, and are based on various scientific theories. The differences are negligible, but you need to know them. Our calculator follows the actual Robinson formula for calculating adjusted body weight, which we said a little more about earlier.

Calculating adjusted body weight – example

Below we will show you a classic example of how you can calculate a custom body weight.

We will assume that you are an employee in the medical profession, and you need to determine the nutritional needs of a particular patient. The man in question is a male, 175 cm tall and weighing 85 kilograms. We first need to calculate the ideal body weight by entering the data we have. The amount with which the calculator will show us for IBW is 68.90 kilograms, while the value of ABW is 75.34 kilograms. Now we need to enter the obtained data in the formula adopted for the calculation:

AjBW = 68.90kg + (0.4 \cdot (75.34kg - 68.90kg))

AjBW = 68.90kg + 0.4 \cdot 6.44kg

AjBW = 68.90kg + 2.576kg = 71.47kg

From the obtained results of adjusted body weight, with the help of our calculator, we can conclude that when it comes to setting a daily diet, this person should be approached as if he weighed 71.47 kilograms.

Limitations of the adjusted body weight calculator

When using this adjusted body weight calculator, it is essential to mention that it is not suitable for all situations you may find yourself in. As already mentioned, it can help you better if you use it only when the excess weight of the selected subjects comes from adipose tissue. Many athletically active people have a higher body weight than you can deduce based on their appearance. Why is that so? Well, the answer to that question is straightforward; it is precisely because the BMI values in these people are above a healthy level. All that excess weight is a lean part of the muscle tissue. In such cases, calculating the adjusted body weight is unnecessary. Another point where it is not recommended to use this calculator is during pregnancy. This natural process in the female body can significantly affect body weight, and these values, in this case, cannot be accurately measured.

When to use adjusted body weight?

This measure is applied to people with specific health problems such as edema, chronic kidney disease, obesity, especially for people who have diabetes and need to align their weight loss program with their habits.

Adjusted body weight can help your metabolism
Adjusted body weight can help your metabolism

How does your body adjust to weight loss?

One of the critical components of leading a healthy life is caring for and controlling your weight. Many people strive to maintain a healthy weight daily, with proper diet and activities, while most of the world’s population suffers from overweight or obesity. The process of losing weight is more precisely possible for everybody, and you need to understand how your body reacts to that process. On this seemingly very easy but complex journey, your metabolism will slow down significantly the more you exercise and manage your calorie intake. The accompanying reaction will be the one that will affect hunger hormones, which will additionally encourage you to eat more often because you are losing weight at the same time. In addition to hormones and metabolism, your neural connections will also fight weight loss, your genetic predispositions, etc. Weight loss can be affected by both your emotional state and the appearance of your body, which may not change at the rate you expect.

Can adjusted body weight be used for obesity assessment?

Since the presented calculator is closely related to obesity, it can also help you determine the diet and nutritional intake for people who are struggling with this health condition. Many healthcare facilities use different methods to assess needs in such cases. It is the measure of calculating the adjusted body weight that medical experts have proposed as one of the ways to improve the accuracy of the results obtained when calculating energy consumption in obese people. Many studies have shown that the accuracy of the adjusted body weight formula results is superior to some traditional prediction equations. In obesity, adjusted body weight refers to a weight that represents metabolically inactive body tissue. You can also apply the calculation formula to prevent overfeeding in critically obese persons and cases where hypocaloric feeding is allowed to particular persons.


1. What is the ideal body weight?

A person who has a body mass index of fewer than 18.5 means that person has a lower body weight. You would value the ideal body weight between 18.5 and 24.9. Anything over 25 is labeled as overweight, while values above 30 are indicators of obesity.

2. What is the formula for calculating lean body weight?

Your lean body mass is calculated by subtracting the weight from your total weight from your body fat, which means that when you remove the percentage of body fat you have from your total weight, you get the amount of lean body weight. You can also use our body fat percentage calculator to calculate that percentage, to get more precise results.