BMI Calculator
Calculate your Body Mass Index instantly with health classification, ideal weight range, and personalized health insights.
📖 About BMI Calculator
Body Mass Index (BMI) is the most widely used screening tool for weight assessment. Calculated as weight (kg) ÷ height² (m²), BMI provides an initial indication of health risk. While not a direct measure of body fat, it correlates with health outcomes in large populations and is used globally by doctors, nutritionists, and health researchers.
📜 History
The BMI formula was developed by Belgian mathematician Adolphe Quetelet between 1830–1850. The term "Body Mass Index" was coined by Ancel Keys in 1972. The World Health Organization adopted BMI as the standard obesity measurement in 1995.
🎯 Common Uses
- Health screening at doctor visits
- Fitness goal setting
- Insurance risk assessment
- Weight management monitoring
- Dietary planning
- Research and epidemiology
FAQ's
❓ What is a normal BMI?
A normal BMI is 18.5–24.9. Below 18.5 is underweight, 25–29.9 is overweight, and 30+ is obese per WHO standards.
❓ How is BMI calculated?
BMI = weight(kg) ÷ height²(m²). Example: 70kg at 1.75m = 70 ÷ (1.75×1.75) = 22.9 BMI.
❓ Is BMI accurate?
BMI is a useful initial screening tool but does not account for muscle mass, age, or ethnic differences. Athletes may show high BMI despite low body fat.
❓ What BMI is considered obese?
A BMI of 30 or higher is classified as obese. BMI 30–34.9 is Class I obesity, 35–39.9 is Class II, and 40+ is Class III (severe obesity).