BMI Formula:
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Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. BMI provides a reliable indicator of body fatness for most people.
The calculator uses the standard BMI formula:
Where:
Explanation: BMI is calculated by dividing weight in kilograms by height in meters squared. The result places you in one of four categories: Underweight, Normal weight, Overweight, or Obese.
Details: BMI is a simple, inexpensive screening method for weight category—underweight, healthy weight, overweight, and obesity. It can help identify potential weight problems in adults.
Tips: Enter weight in kilograms and height in meters. For height, you can convert from cm to m by dividing by 100 (e.g., 175 cm = 1.75 m). All values must be valid (weight > 0, height > 0).
Q1: What are the BMI categories?
A: Underweight (BMI < 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and Obese (≥30).
Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and those with muscular builds, and underestimate it in older persons who have lost muscle mass.
Q3: What is a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy. However, optimal BMI may vary by age, sex, and ethnicity.
Q4: Should children use this calculator?
A: No, children and teens need age- and sex-specific percentiles rather than the adult BMI categories.
Q5: What are alternatives to BMI?
A: Waist circumference, skinfold thickness measurements, and more advanced techniques like DEXA scans can provide additional information.