What Is Body Mass Index (BMI)?

Body mass index (BMI) uses height and weight to assess whether weight falls in a commonly used healthy range for adults. WHO uses it widely; it equals weight in kilograms divided by height in meters squared.

BMI does not show full body composition—muscle, bone density, fat distribution, and genetics all matter. Treat results as information only; clinical decisions need a qualified professional.

What the DiyetisyenPRO BMI Tool Offers

This calculator goes beyond a single number:

Live updates: BMI refreshes as you type or move sliders—no extra button.
Category scale: Visual band for underweight, healthy, overweight, obese, or severely obese with numeric cutoffs.
Healthy weight range: Weight bounds for BMI 18.5–24.9 for your height.
Gap to range: Approximate kg to gain or lose if you are outside the healthy band.
BMR: With age and sex, Mifflin-St Jeor estimates basal calories.
Age notices: Messages that BMI interpretation differs under 18 and over 65.
Sex-specific notes: Short plain-language interpretation by category.
Dietitian path: Link to find a professional on DiyetisyenPRO.

BMI Categories

Underweight: Below 18.5 — possible undernutrition risk.
Healthy: 18.5–24.9 — commonly accepted healthy range for adults.
Overweight: 25–29.9 — lifestyle changes may be discussed.
Obese: 30–34.9 — specialist support often recommended.
Severely obese: 35+ — higher health risk; seek professional advice.

When BMI May Mislead

Athletes, bodybuilders, pregnant and breastfeeding individuals, and some older adults may need composition or clinical assessment instead. Under 18, growth charts apply; this tool uses adult WHO classes.

Using Your Results

BMI, healthy range, and BMR help frame goals, but sustainable change also needs balanced nutrition, adequate protein, activity, and personal medical history.

Book online or in-person support through DiyetisyenPRO to turn your numbers into an individualized plan. Expert guidance beats any generic calculator alone.

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