Healthy BMI range is between 18.5 - 24.9 for young people and adults with a healthy weight. BMI is the measure of human body fat based on weight and height. Though BMI does not have a perfect measure, it is calculated by dividing your weight (kilograms), by height^2 (meters). This is particularly the case when a doctor is assessing obesity and overweight at the population level.

Down at the personal level, there are no limitations because it can be affected by gender, age, ethnicity, and lifestyle. Besides, BMI does not differentiate between lean mass and fat mass. In fact, it does not even recognize fat distribution in the body.

Equipment required

You will need two standard measurements (weight) and height. To get these, you have to use a stadiometer and weighing scale.


Using a stadiometer and weighing scale, take the correct reading for height in (meters) and weight (kilograms). Then apply the formula for BMI given below.

BMI = mass (kg) / height^2 (meter)

Healthy Weight Range = BMI between 18.5 and 25.

The following classification is used to guide people know how far they have deviated from the healthy BMI range.

Classification BMI (kg/m^2) Risk of co-morbidities (Health consequences)
Underweight <18.50 Low (but possibly increased risk of other clinical problems)
Normal BMI range (Healthy Weight) 18.50 - 24.99 Average
Overweight >25.00  
Pre-obese 25.00 - 29.99 Increased
Obese class 1 30.00 - 34.99 Moderate
Obase class 2 35.00 - 39.99 Severe
Obese class 3 >40.00 Very severe

Target population

The healthy BMI range is used mainly on young people and adult populations.

Pros of Healthy BMI range

Cons of healthy BMI range

Final thought

After a long time of struggling with different formulae that only gave estimates within a very wide range, healthy BMI has finally provided a better solution. Though it still lacks in some ways because it does not factor all aspects of human weight such as lean mass and fat mass, it is the best among all other formulae.


1. Rothman, K. BMI-related errors in the measurement of obesity. International Journal of Obesity (2008) 32, S56–S59

2. Reilly JJ. Diagnostic ability of the BMI for age in pediatrics. Int J Obes Relat Metab Disord 2006; 30: 595–597.

3. Willett WC. Anthropometric measures and body composition. Nutritional Epidemiology, 2nd edn. Oxford University Press: New York, 1998, pp 244–272.

4. McCarthy HD, Jarrett KV, Crawley HF. The development of waist circumference percentiles in British children aged 5.0–16.9 year. Eur J Clin Nutr 2001; 55: 902–907.

5. Lohman TG, Roche AF, Martorell R (eds) Anthropometric Standardization Reference Manual. Human Kinetics: Champaign, IL, 1988, pp 1–177.

6. Peterson, M., Diana M., George B., and Steven B. Universal equation for estimating ideal body weight and body weight at any BMI. Am J Clin Nutr May 1, 2016 103: 1197-1203