BMI is a general screening indicator. Consult a medical professional for individual health assessments and athletic body composition evaluations.
- 1Select your measurement unit system: Metric (kg / cm) or Imperial (lbs / ft-in).
- 2Enter your body weight and height into the labelled fields.
- 3View your calculated Body Mass Index score, standard category classification, and colour-coded health gauge meter.
Body Mass Index (BMI) is a statistical screening ratio that categorizes body weight relative to height. Established by the World Health Organization (WHO), BMI provides a standardized population-level estimate for screening weight categories.
Divide weight in kilograms by height in metres squared.
BMI = Weight (kg) / [Height (m)]² | Example: 70kg / (1.75m)² = 22.9Multiply weight in pounds by 703, then divide by height in inches squared.
BMI = [ Weight (lbs) × 703 ] / [ Height (in) ]² | Example: (154 × 703) / 69² = 22.7Underweight (<18.5) | Normal weight (18.5–24.9) | Overweight (25–29.9) | Obesity (≥30)
Normal Weight Range: 18.5 ≤ BMI < 25BMI = 70 / (1.75 × 1.75) = 70 / 3.0625 = 22.86BMI = (154 × 703) / 69² = 108,262 / 4,761 ≈ 22.7BMI = 95 / (1.75)² = 95 / 3.0625 ≈ 31.0- Screening Metric Only: BMI is a population screening ratio and does not directly measure body fat percentage or muscle mass.
- Athletic Limitation: Muscular athletes or weightlifters may register a high BMI despite low body fat because muscle mass is denser than fat.
- Not a Medical Diagnosis: BMI scores provide statistical guidance only and do not constitute individual clinical health assessments.
What does BMI measure?
BMI measures weight relative to height squared. It serves as a general screening tool to estimate weight status across adult populations.
Why can BMI be misleading for athletes?
Because BMI cannot distinguish between lean muscle weight and fat weight, dense muscle mass can result in a high BMI category without excess fat.
What is considered a normal BMI range?
According to World Health Organization (WHO) standards, a BMI between 18.5 and 24.9 is classified as normal or healthy weight for adults.
What are the exact category cut-offs used?
Underweight below 18.5, normal from 18.5 up to (but not including) 25, overweight from 25 up to 30, and obesity at 30 and above.
Medical Disclaimer
The results provided by this BMI calculator are estimates based on standard formulas and are provided for informational and educational purposes only. BMI is a reference measure and does not constitute a medical diagnosis or a complete assessment of health or body composition.
The calculation does not account for individual factors such as muscle mass, body fat distribution, certain medical conditions, medications, pregnancy, age, or other personal circumstances that may affect how the result should be interpreted. Do not use this result to make significant decisions about your diet, weight, or health without consulting a healthcare professional.
This tool does not provide medical advice, diagnosis, or personalised treatment.