NutriCalc.fit
BMI Calculator
Calculate your Body Mass Index (BMI) to assess your weight category and potential health risks.
Enter Your Measurements
BMI is calculated using your weight and height to determine your body fat percentage category.
Ready to Calculate
BMI is calculated using your weight and height to determine your body fat percentage category.
About BMI
Formula
BMI = weight (kg) ÷ height (m)²
BMI Categories
BMI Calculator for Health and Nutrition Professionals
Easily calculate Body Mass Index (BMI) to screen for weight categories and support nutrition assessments in clinical or field settings.
Understanding BMI in Clinical Practice
Body Mass Index (BMI) is one of the most widely used screening tools to estimate weight status and potential health risks.
For healthcare and nutrition professionals, it offers a quick, standardized metric to classify underweight, normal weight, overweight, or obesity.
However, BMI alone cannot distinguish between lean muscle and fat mass. For this reason, it should be interpreted alongside other measures such as waist-to-hip ratio, body fat percentage, and medical history.
How to Use This BMI Calculator
Enter the patient's weight in kilograms.
Enter the patient's height in centimeters.
Click Calculate to obtain the BMI value.
Review the BMI category to guide further evaluation or interventions.
BMI Categories (WHO)
| Category | BMI Range |
|---|---|
| Underweight | <18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25 – 29.9 |
| Obesity I | 30 – 34.9 |
| Obesity II | 35 – 39.9 |
| Obesity III | ≥40 |
Frequently Asked Questions
What is a healthy BMI for adults?
A healthy BMI for most adults is between 18.5 and 24.9 kg/m², according to the World Health Organization (WHO).
How often should BMI be monitored?
For patients undergoing weight management or clinical follow-up, BMI can be monitored at each consultation or monthly.
Is BMI accurate for athletes?
BMI may overestimate fatness in athletes with high muscle mass. Complement BMI with body composition assessments.
Does BMI vary by age?
While the calculation is the same, older adults may require complementary measures due to changes in body composition.
Scientific References
World Health Organization (WHO). BMI Classification and Risk.
National Institutes of Health (NIH). Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults.
Deurenberg P, et al. "Body mass index as a measure of body fatness: age- and sex-specific prediction formulas."