BMI Calculator — Body Mass Index with Health Context
Calculate your Body Mass Index instantly with health context and weight category classification. Understand what your BMI means and its limitations as a health metric.
Frequently Asked Questions
How is BMI calculated?
BMI is calculated by dividing your weight in kilograms by your height in meters squared (kg/m²). For example, a person weighing 70 kg and 1.75 m tall has a BMI of 22.9. This calculator handles unit conversion automatically — just enter your height and weight in any unit.
What is a healthy BMI?
According to the WHO, a healthy BMI ranges from 18.5 to 24.9. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is obese. However, BMI doesn't account for muscle mass, bone density, or body fat distribution.
Is BMI accurate?
BMI is a useful screening tool but has important limitations. It overestimates body fat in muscular individuals and underestimates it in older adults who have lost muscle mass. Consider pairing it with waist circumference or body fat percentage for a fuller picture.
Put your numbers into action
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