Free BMI Calculator
Free BMI Calculator
Calculate your Body Mass Index (BMI) instantly and get personalized health insights. Understand your health status with science-backed recommendations.
Calculate
Enter your measurements to get your Body Mass Index and personalized health insights
Understanding BMI Categories
Understanding BMI Categories
Learn what your BMI score means for your health and wellbeing with medically accurate WHO/CDC categories.
Severely Underweight
Severely below normal weight. Immediate medical consultation strongly recommended.
Underweight
Below normal weight range. Consider consulting a healthcare provider for nutritional guidance.
Normal (Healthy) Weight
Healthy weight range associated with lower risk of chronic diseases (WHO/CDC guidelines).
Overweight
Above normal weight range. Focus on balanced diet and regular exercise.
Obesity, Class I
Class I obesity. Increased risk for various health conditions. Professional medical guidance recommended.
Obesity, Class II
Class II obesity. Significantly increased health risks. Medical supervision strongly recommended.
Obesity, Class III
Class III (severe/morbid) obesity. Highest health risks. Immediate comprehensive medical care needed.
BMI Formula & Medical Standards
Our calculator uses the official WHO and CDC formulas for medical accuracy.
Metric Formula
Standard metric calculation used in medical literature and WHO guidelines.
Imperial Formula
U.S. standard calculation with the 703 conversion factor for medical accuracy.
Medical Standards & Sources
Category Standards
- • World Health Organization (WHO)
- • U.S. Centers for Disease Control (CDC)
- • National Heart, Lung, and Blood Institute
Limitations
- • Does not distinguish muscle vs. fat mass
- • May vary by ethnicity and age
- • Screening tool, not diagnostic
What is BMI and how is it calculated?
BMI (Body Mass Index) is a measure that uses your height and weight to determine if you're in a healthy weight range. It's calculated by dividing your weight in kilograms by your height in meters squared (kg/m²).
Is BMI accurate for everyone?
BMI is a useful screening tool, but it has limitations. It doesn't distinguish between muscle and fat mass, so athletes or very muscular individuals may have a high BMI without excess body fat. Always consult healthcare professionals for comprehensive health assessment.
What should I do if my BMI is outside the normal range?
If your BMI is outside the normal range, consider consulting with a healthcare provider or registered dietitian. They can help create a personalized plan for achieving and maintaining a healthy weight through proper nutrition and exercise.
Take Control of Your Health Journey
Ready for personalized health insights beyond BMI? Uara.ai analyzes your wearables, labs, and lifestyle data to provide comprehensive longevity recommendations.