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← Back to DashboardBMI (Body Mass Index) is a simple way to estimate whether your weight is in a healthy range for your height. It's widely used by doctors and health organizations as a quick screening tool — not a diagnosis, but a useful starting point.
| BMI Range | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Normal weight |
| 25.0 – 29.9 | Overweight |
| 30.0 and above | Obese |
The formula is straightforward: divide your weight in kilograms by your height in meters squared. For imperial measurements, the same formula is used with a conversion factor (weight in lbs ÷ height in inches² × 703).
BMI is a useful screening tool but has real limitations. It doesn't account for muscle mass, bone density, age, or where body fat is distributed. Some common examples where BMI can be misleading:
If your BMI falls outside the normal range, talk to a doctor before drawing any conclusions — especially if you're very active or have a muscular build.
Not necessarily. Athletes often have a high BMI due to muscle mass. BMI is a screening tool, not a definitive health measure. A doctor will consider many other factors alongside BMI.
The standard BMI ranges (18.5–24.9 for normal weight) apply to both men and women. However, women naturally carry more body fat than men at the same BMI, so some clinicians use body fat percentage alongside BMI for a fuller picture.
Since BMI depends on height (which doesn't change for adults), tracking changes monthly is usually sufficient. Daily fluctuations in weight are mostly water and don't reflect real changes in body composition.
No. Your height and weight are only used locally in your browser to calculate the result. Nothing is stored or sent anywhere.