⚖️ BMI Calculator
Quick answer
BMI (Body Mass Index) is a person's weight in kilograms divided by the square of their height in metres: BMI = kg ÷ m². The World Health Organization classifies adults as underweight below 18.5, normal from 18.5 to 24.9, overweight from 25 to 29.9, and obese at 30 or above. BMI is a screening measure, not a diagnosis.
Your Body Mass Index
Category: Normal (healthy)
| Healthy weight range for your height | 56.7 – 76.3 kg |
| Underweight | Below 18.5 |
| Normal | 18.5 – 24.9 |
| Overweight | 25 – 29.9 |
| Obese | 30 and above |
This is general information only and is not medical advice. Talk to a doctor for a full health assessment.
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How to use the BMI Calculator
- Choose metric (kg/cm) or imperial (lb/in) units.
- Enter your weight and your height.
- Click "Calculate BMI" to see your BMI number.
- Check your category and the healthy weight range for your height.
Frequently asked questions
What is a healthy BMI?
For most adults, a BMI between 18.5 and 24.9 is classified as normal (healthy). Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is obese, according to the World Health Organization.
Is BMI accurate for athletes and children?
BMI can overestimate body fat in muscular athletes and is not used directly for children and teens, whose results are read on age-and-sex growth charts instead. It also does not measure body fat distribution. This tool is general information, not medical advice.
How do I calculate BMI in imperial units?
Divide weight in pounds by height in inches squared, then multiply by 703. Example: 154 lb at 69 in → 154 ÷ 4761 × 703 ≈ 22.7.