BMI calculator for kids, child and adults

Our BMI calculator will help you quickly calculate your body mass index and determine which weight category your or your childrens’ score falls into.

BMI Healthy Weight Calculator




Weight Class

Before using the data obtained using this calculator, please consult with doctor.

The correct interpretation of Adult BMI results

The body mass index (BMI) serves as a statistical indicator that allows you to determine the weight category of a person. Moreover, it shows potential risks of various diseases when the indicators deviate from a healthy value.

In order to find out your body mass index, you can use our BMI calculator. In addition to the calculator, you can find a description of the main categories and recommendations for different cases below.

Very severely underweight<15
Severely underweight15-16
Normal or healthy weight18.5-25
Obese class 235-40
Obese class 3>40


Being underweight can significantly increase the risks of various diseases when the immune system may become weak due to a lack of nutrients. If your BMI value is below 18.5, then you belong to this category. Being in this category, a person can have the following symptoms and diseases:

  • Decreased physical stamina
  • Weak immunity
  • Osteoporosis
  • Anemia
  • Increased likelihood of stroke
  • Delayed physical and mental development

The following steps can help you gain healthy weight.

  • Making an appointment with a doctor who will prescribe the necessary tests for you and select the optimal meal plan
  • Adding high-calorie foods and nutrients to your diet
  • Doing different exercises to normalize metabolism and build muscle mass.

Healthy Weight

If your BMI is between 18.5 – 25, then you are in the Healthy Weight category. Congratulations, keep it up 🙂

Maintaining a healthy weight and an active lifestyle will keep you energetic, resilient and help avoid many of the diseases associated with obesity.

Overweight and Obesity

You are in the obese category if your BMI is over 35. In this case, you should immediately make an appointment with a doctor and take the necessary measures to normalize your weight.

Obesity can lead to increased risks of the following diseases:

  • asthma
  • type 2 diabetes
  • hypertension
  • coronary artery disease
  • gallbladder disease
  • respiratory problems
  • some types of cancer

To return your body to a healthy weight, you can take the following steps:

  • Create a balanced diet. If you find it challenging to make a meal plan for yourself, you can consult with a nutritional specialist. 
  • Increase the time of daily physical activity. You can add walking (for several hours), running, swimming or any other activity that you like.
  • Talk to your doctor about choosing a treatment program for you. He may prescribe medications, diet or surgery.

The correct understanding of Children’s BMI results

If you want to determine the weight category of your children, you need to follow the next steps:

  • Determine BMI using the standard formula
  • Get percentile using an appropriate BMI-for-age percentile chart. The chart for boys and girls can be found on the CDC website
  • Using the table below, you can discover which category your child’s BMI falls into
Weight Status CategoryPercentile Range
Underweight> 5 %
Healthy weight5-85 %
Overweight85-95 %
Obese> 95 %

Limitations of the BMI formula

Please note that the formula only accounts person’s weight and height and does not take into account the actual volume of adipose tissue and its location in the body. In addition, the calculations do not take into account the types of activity that a person is engaged in, the environment in which he lives and physical disabilities. For example, professional athletes may have a BMI above 25, but in this case, they have increased muscle mass rather than fat mass.