BMI Calculator

How to use the BMI Calculator

1. Select your preferred unit system: metric (kg/cm) or imperial (lbs/inches).
2. Enter your height and weight.
3. View your BMI score, WHO category, and position on the visual scale instantly.
4. Use the result as a general guide and consult a healthcare professional for personalized advice.

What BMI does and doesn't actually measure

BMI doesn't distinguish between muscle mass and fat mass, which is why a muscular athlete can register as "overweight" by BMI despite having low body fat, and why an older adult with reduced muscle mass can register as "normal" despite having a higher-than-ideal body fat percentage. It's a genuinely useful quick screening tool at a population level, and it correlates reasonably with health risk on average across large groups, but for an individual assessment, it should be considered alongside other measures (like body composition, waist circumference, or a broader clinical evaluation), not treated as a standalone diagnosis.

Frequently asked questions

Is BMI accurate for everyone?

No. It's a general screening estimate that doesn't account for muscle mass, bone density, age, or body composition, so it's less reliable for athletes, older adults, and some other groups than it is for the general population it was statistically derived from.

What are the standard WHO BMI categories?

Underweight (below 18.5), normal weight (18.5-24.9), overweight (25-29.9), and obese (30 and above). These thresholds are population-level guidelines, not individual clinical diagnoses.

Should I make health decisions based on my BMI alone?

No. Use it as one general data point, and talk to a doctor or qualified health professional for a fuller picture that accounts for your individual health history and body composition.