Calculate your Body Mass Index instantly
| Category | BMI Range |
|---|---|
| Severe Underweight | < 16.0 |
| Underweight | 16.0 - 18.4 |
| Normal Weight | 18.5 - 24.9 |
| Overweight | 25.0 - 29.9 |
| Obese Class I | 30.0 - 34.9 |
| Obese Class II | 35.0 - 39.9 |
| Obese Class III | ≥ 40.0 |
The Body Mass Index (BMI) calculator helps you assess whether your weight is in a healthy range for your height. It uses the standard formula: BMI = weight in kilograms divided by height in meters squared. Our tool supports both metric (kg, cm) and imperial (lbs, feet/inches) units with easy toggle switches.
After calculating your BMI, the tool shows a visual gauge indicating where you fall on the spectrum from underweight to obese. It also provides general health tips based on your category. BMI is widely used by health professionals as a quick screening tool, though it does not account for muscle mass, bone density, or body composition. For a complete health assessment, always consult with a qualified healthcare provider. This calculator is for informational purposes only and does not constitute medical advice.
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BMI (Body Mass Index) is weight in kilograms divided by height in metres squared — BMI = kg ÷ m² — and is used as a quick screening measure for weight category, not as a diagnosis.
SnoopTool's BMI calculator accepts metric or imperial units and shows where you fall on the WHO categories. BMI ignores muscle mass and body composition, so athletes and older adults can be mis-categorised; treat it as one signal among several.
| Formula (metric) | BMI = weight (kg) ÷ height (m)² |
|---|---|
| Formula (imperial) | BMI = 703 × weight (lb) ÷ height (in)² |
| WHO categories | Underweight < 18.5 · Normal 18.5–24.9 · Overweight 25–29.9 · Obese ≥ 30 |
| Asian-Indian cut-offs | Overweight ≥ 23, obese ≥ 25 (per Indian consensus guidelines) |
| Limitation | Does not distinguish muscle from fat, or where fat is stored |
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