BMI Calculator
Enter your height and weight to calculate your Body Mass Index and see which weight category you fall into.
BMI = weight(kg) ÷ height(m)². Use this calculator to quickly find your BMI and understand which weight category you fall into (underweight, normal, overweight, or obese).
Understanding Your BMI
Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = weight(kg) ÷ height(m)². BMI is used as a screening tool to categorize weight status that may lead to health problems, but it is not a diagnostic tool.
BMI values are generally interpreted as follows: - Below 18.5: Underweight - 18.5-24.9: Normal weight - 25.0-29.9: Overweight - 30.0 and above: Obesity
- BMI does not account for muscle mass, bone density, or overall body composition.
- Athletes with high muscle mass may have a high BMI but low body fat.
- For children and teenagers, BMI percentiles are used, which account for age and sex.
- Always consult a healthcare professional for personalized advice about weight and health.
Worked Example
Example: A person who is 1.75 m tall and weighs 70 kg:
BMI = 70 ÷ (1.75 × 1.75) = 70 ÷ 3.0625 = 22.86
A BMI of 22.86 falls within the "Normal weight" category (18.5-24.9).
Limitations of BMI
While BMI is a useful population-level screening tool, it has limitations:
1. It does not distinguish between muscle and fat mass. 2. It may not accurately reflect body fat for athletes, children, the elderly, or people with medical conditions. 3. Waist circumference and other measurements can provide additional health information. 4. BMI should be considered along with other health markers, not as a standalone diagnostic.
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Open calculator →Frequently Asked Questions
What is a healthy BMI range?
A healthy BMI range for most adults is 18.5 to 24.9. However, this can vary based on age, sex, and ethnicity.
Does BMI apply to everyone the same way?
No. BMI may not be accurate for athletes with high muscle mass, children, teenagers, older adults, or pregnant women. These groups may need different assessments.
How is BMI different from body fat percentage?
BMI is a simple ratio of weight to height, while body fat percentage directly measures the proportion of fat in your body. Body fat percentage is typically measured using specialized scales, water displacement, or bioelectrical impedance.
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