| Category | BMI range | Advice |
|---|---|---|
| Underweight | < 18.5 | Gain weight, improve nutrition |
| Normal | 18.5 – 24.9 | Keep balanced diet & exercise |
| Overweight | 25 – 29.9 | Cut calories, add cardio |
| Obese | ≥ 30 | Lose weight safely, see a doctor |
BMI Calculator Guide
1
Choose metric or imperial, enter height and weight
2
Click "Calculate BMI" for an instant value and category
3
Check the table and advice to learn your healthy weight range
📐How BMI is calculated
- Formula: BMI = weight (kg) ÷ height (m)²
- e.g. 70kg, 1.75m → 70 ÷ (1.75×1.75) ≈ 22.9
- Imperial input is auto-converted to metric
💡Health tips
- The normal range (18.5-24.9) with regular exercise is healthiest
- BMI does not distinguish muscle from fat — athletes, use as reference
- Adult BMI does not apply to pregnant women, elderly or children
BMI is a common indicator of whether your weight is healthy, quickly flagging underweight, normal, overweight or obese as a starting point for weight management.
🔒 Height and weight are computed locally in your browser, never uploaded; results are for reference only and do not replace professional medical advice.