Reviewed by Mohammad Nazri Zulkafli, MD and Physician Vong U Chan
Weight Calculation: Identifying Different Methods to Measure Healthy Body Weight
Published | 6 min read
An article that lists the different methods to calculate your ideal body weight.
Have you ever stood in front of a mirror, looking at the result on your weighing scale, and asking yourself, “Is my weight ideal? Do I need to lose some weight?” Identifying weight goals based on your body type should be the first step towards a healthy life. Weight calculation using a weight calculator is a good way to start.
In addition, it’s also essential for you to understand the 3 distinct body types — ectomorph, mesomorph and endomorph.
Ectomorphs struggle with weight gain and are typically lean with minimal body fat and muscle. Mesomorphs can gain or lose weight quickly whilst having a strong, athletic figure.
Endomorphs, meanwhile, have a large amount of body fat and muscle and can gain weight easily. In Traditional Chinese Medicine (TCM), people described as endomorphs are identified as those with a qi or yang deficiency body constitution.
“For people with a phlegm-dampness body constitution, I would categorise them as meso-endomorph. They tend to be slightly obese, and their body shape is what we call an apple shape. Their weight gain mainly focuses around the abdomen area,” says Eu Yan Sang’ TCM physician Vong U Chan.
If you want to know the best way to measure your ideal weight, find out more about these 6 different methods that you can use.
Weight Calculators to Determine Ideal Body Weight
There are weight calculation methods you can use to measure your body weight. Using weight calculators is one of the simplest way to do this. Each weight calculator is accompanied by a unique set of pros and cons – the final choice is in your hand.
Body mass index (BMI) calculator
A body mass index (BMI) calculator can calculate your body fat mass based on your current height and weight and is suitable for both men and women. A BMI calculator uses several categories to identify the risk of negative health implications.
These Asian BMI categories include underweight (BMI below 18.5), normal weight (BMI between 18.5 and 22.9), overweight (BMI between 23.0 and 24.9), and obese (BMI above 25). Alternatively, the BMI Percentile Calculator can calculate the body fat of children and teenagers between the ages of 2 and 19.
Yet, according to physician Vong, TCM does not only measure your health based on the numerical body weight assessment. It also considers everyday lifestyle indicators such as your appetite, bowel movement, energy levels, and sleep quality.
Relative fat mass (RFM) calculator

Like a BMI calculator, a relative fat mass (RFM) calculator’s use is to measure your body fat. However, this weight calculator uses height and waist circumference to determine your correct fat percentage. Some people find that it is more accurate than a BMI calculator.
To get a correct measurement of your height, ensure that your buttocks, upper back, and back of your head are touching a vertical surface. On the other hand, ensure that your measuring tape stretches around the area of your body above the left and right ilium. Ilium refers to the largest and uppermost part of your hip bone.
Robinson formula
The Robinson formula for calculating your ideal body weight is based on the belief that the ideal body weight of a man who is 5-feet-tall (152 cm) should be 52 kilograms, while a woman should be 49 kilogrammes.
If you are taller than 5 feet, you should adhere to the following equations:
- For men, the suggestion is to add 1.9 kilograms to the base weight per inch (2.5 cm) above 5 feet
- For women, the suggestion is to add 1.6 kilograms to the base weight per inch above 5 feet
It is worth noting that the Robinson formula is effective if you are of average height. Therefore, it’s not a reliable way to get the ideal body weight of very tall or very short people.
Miller formula
The Miller formula was derived in 1983 and is based on the belief that a man who is 5 feet (152 cm) should be 56.2 kilograms, and a woman 53.1 kilograms. For every additional inch (2.5 cm) on top of the 5 feet, this formula suggests the addition of 1.41 kilograms and 1.36 kilograms to a man and woman’s body weight, respectively.
This formula is useful for calculating your ideal body weight during an emergency. For instance, when administering a drug to or adjusting the ventilator setting for a patient, the given estimate will not be conclusive since it leaves out many crucial factors.
Devine Formula

The Devine formula is arguably one of the most applied formulas to date. Originally established to calculate medication dosages, this formula uses a measure of your height to determine your body weight. It is based on the belief that a man’s weight at 5 feet (152 cm) should be 50 kilograms, and a woman 45.5 kilograms.
The weight calculator also suggests adding 2.3 kilograms for every extra inch (2.5 cm) to a man or woman’s body weight.
Hamwi Formula
The Hamwi formula was established in 1964 by Dr G.J. Hamwi, and is computed using inches and pounds. It prioritises the belief that a 5-feet tall (152 cm) woman should weigh 100 pounds, and a man 106 pounds.
At the same time, for every inch (2.5 cm) over 5 feet, you should add 5 pounds (2.3 kilograms). But if you are shorter, you should subtract 5 pounds for every inch below 5 feet.
The Hamwi formula also uses the ‘body frame’ concept to determine your actual ideal body weight. The adjusted body weight concept requires a measuring tape to get the correct reading of your wrist.
If your wrist measures 7 inches (18 cm), you have a medium-sized body frame and should not adjust the ideal body weight. If your wrist is bigger than 7 inches, you need to add 10%, and if your wrist is smaller than 7 inches, you need to subtract 10% of your ideal body weight to the formula.
What’s most important is ensuring that you lead a healthy lifestyle. That means, eat right and exercise. An oatmeal beverage is a good source of protein and fibre. Because of this, it’s beneficial for regulating your cholesterol levels and promoting weight control.
For gut health, taking a probiotic supplement containing 100 million friendly Lactobacillus acidophilus bacteria can support a healthy digestive system.
There are different ways of working out your ideal weight using weight calculation methods. The BMI and RFM calculators have more frequent uses, but combining the use of a weight calculator with different formulas may be the best way to get an accurate idea of whether you are at your healthiest or not.
References
- Harvard T.H Chan. Healthy Weight. [Accessed 2 July 2021]
- University of Houston. The 3 Somatypes.[Accessed 2 July 2021]
- NHS. 2020. Underweight adults. [Accessed 2 July 2021]
- Centers for Disease Control and Prevention. 2020. Adult BMI Calculator.[Accessed 2 July 2021]
- Centers for Disease Control and Prevention. 2021. BMI Percentile Calculator for Child and Teen.[Accessed 2 July 2021]
- DQYDJ. Body Fat Estimate Calculator using Waist to Height Ratio (RFM).[Accessed 2 July 2021]
- BMI-Calculator.net. Ideal Body Weight – J. D. Robinson Formula (1983). [Accessed 2 July 2021]
- BMI-Calculator.net. Ideal Body Weight – B. J. Devine Formula (1974). [Accessed 2 July 2021]
- BMI-Calculator.net. Ideal Body Weight – GJ Hamwi Formula (1964). [Accessed 2 July 2021]
- NCBI. Weight Management: State of the Science and Opportunities for Military Program. [Accessed 2 July 2021]
- Centers for Disease Control and Prevention. 2021. Adult Obesity Causes & Consequences.[Accessed 2 July 2021]
- Northern Illinois Vein Clinic. 2019. Why Good Blood Circulation is Vital to Your Health. [Accessed 2 July 2021]