WHO Formula
Accurate BMI using approved formulas
Visual Chart
See your category at a glance
Metric & Imperial
kg/cm or lbs/ft/in
Health Guidance
Personalized recommendations
Complete Guide to BMI
Body Mass Index (BMI) is a widely used metric to assess whether your weight is healthy for your height. It's used by healthcare professionals worldwide as a screening tool to identify potential weight-related health problems.
BMI Formula
Metric: BMI = weight (kg) ÷ height (m)²
Imperial: BMI = (weight (lbs) ÷ height (in)²) × 703
BMI Categories
| BMI Range | Category | Health Risk |
|---|---|---|
| Below 18.5 | Underweight | Increased risk |
| 18.5 – 24.9 | Normal Weight | Lowest risk |
| 25 – 29.9 | Overweight | Increased risk |
| 30 and above | Obese | High risk |
Limitations of BMI
- Doesn't distinguish between muscle and fat mass — athletes may score high despite being healthy
- Doesn't account for fat distribution — belly fat poses more risk than fat elsewhere
- Age and gender not factored in
- May not apply equally across all ethnic backgrounds
How to Use
- Select Metric (kg/cm) or Imperial (lbs/ft/in)
- Enter your weight and height
- Click Calculate BMI for instant results
- Review your category and health recommendations
Frequently Asked Questions
A BMI between 18.5 and 24.9 is considered normal/healthy weight according to WHO standards.
Metric: BMI = weight (kg) ÷ height (m)². Imperial: BMI = (weight (lbs) ÷ height (in)²) × 703.
Not always. BMI may overestimate body fat for muscular athletes since it doesn't distinguish between muscle and fat mass. It's a screening tool, not a diagnostic measure.
Yes, 100% free with no registration, no limits, and no data stored.
If your BMI is outside the 18.5–24.9 range, or you have weight-related health concerns, consulting a healthcare provider is recommended for personalized guidance.
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