Your Measurements
cm
kg
22.5
Normal weight
Healthy weight range: —
BMI Calculator computes Body Mass Index from height and weight in metric (cm/kg) or imperial (ft/in/lbs) units, displays the WHO classification (underweight, normal, overweight, obese), and shows where the result falls on the BMI scale with the healthy weight range for your height.
Body Mass Index is calculated as weight in kilograms divided by height in meters squared (kg/m2). The World Health Organization classifies adult BMI as follows: below 18.5 is underweight, 18.5 to 24.9 is normal weight, 25.0 to 29.9 is overweight, and 30.0 or above is obese. These thresholds were established from population studies correlating BMI with health outcomes.
BMI is widely used in clinical practice, fitness tracking, and public health research because it requires only two measurements and no lab work. It is the standard screening metric used by the CDC and WHO. However, it is explicitly a screening tool — it does not directly measure body fat percentage, distinguish muscle from fat, or account for differences in body composition across age groups, sexes, or ethnicities.
This calculator is provided for informational purposes. For clinical assessment, consult a healthcare professional who can interpret BMI in the context of other measurements and health history.
Height: 175 cm, Weight: 70 kg
Result: BMI: 22.9 — Normal weight. Healthy weight range for this height: 56.7 to 76.4 kg
Height: 5 ft 10 in, Weight: 200 lbs
Result: BMI: 28.7 — Overweight. Would need to be under 174 lbs for normal BMI at this height
Height: 160 cm, Weight: 45 kg
Result: BMI: 17.6 — Underweight. Healthy weight range: 47.4 to 63.9 kg
Is BMI accurate for athletes?
No. Athletes with high muscle mass will have a higher BMI than their body fat percentage warrants, because muscle is denser than fat. A heavily muscled person may be classified as overweight despite low body fat. Body composition measurements like DEXA scans give more accurate results.
Is the BMI scale different for children?
Yes. Children and teenagers use BMI-for-age percentiles rather than the adult classification thresholds, because body composition changes with age. This calculator is designed for adults 18 and older.
Does BMI account for where body fat is stored?
No. Central abdominal fat is a stronger independent risk factor for cardiovascular disease than overall BMI. Waist circumference and waist-to-hip ratio are better predictors of metabolic risk.
Are the BMI thresholds the same for all ethnicities?
Research suggests people of Asian descent have higher disease risk at lower BMI values. Some Asian countries use adjusted cutoffs — overweight starting at BMI 23 instead of 25. Consult your healthcare provider for interpretation in context.
What is the difference between BMI and body fat percentage?
BMI is a proxy calculated from height and weight. Body fat percentage directly measures what fraction of your mass is fat tissue. The two correlate in the general population but diverge significantly for athletes and the elderly.